Robotic surgical tools with torsion cable actuation

ABSTRACT

A robotic surgical tool includes a drive housing having a first end, a second end, and a lead screw extending between the first and second ends, a carriage movably mounted to the lead screw at a carriage nut secured to the carriage, and an activating mechanism including a drive gear rotatably mounted to the carriage and rotatable to actuate the activating mechanism. A torsion cable extends between the drive gear and a drive input arranged at the first end, wherein rotating the drive input rotates the torsion cable and thereby transmits a torsional load along the torsion cable to the drive gear to actuate the activating mechanism.

TECHNICAL FIELD

The systems and methods disclosed herein are directed to roboticsurgical tools and, more particularly to, robotic surgical tools thatincorporate torsion cables the cause actuation of various functions uponrotation.

BACKGROUND

Minimally invasive surgical (MIS) instruments are often preferred overtraditional open surgical devices due to the reduced post-operativerecovery time and minimal scarring. The most common MIS procedure may beendoscopy, and the most common form of endoscopy is laparoscopy, inwhich one or more small incisions are formed in the abdomen of a patientand a trocar is inserted through the incision to form a pathway thatprovides access to the abdominal cavity. The cannula and sealing systemof the trocar are used to introduce various instruments and tools intothe abdominal cavity, as well as to provide insufflation to elevate theabdominal wall above the organs. The instruments can be used to engageand/or treat tissue in a number of ways to achieve a diagnostic ortherapeutic effect.

Each surgical tool typically includes an end effector arranged at itsdistal end. Example end effectors include clamps, graspers, scissors,staplers, suction irrigators, blades (i.e., RF), and needle holders, andare similar to those used in conventional (open) surgery except that theend effector of each tool is separated from its handle by anapproximately 12-inch long shaft. A camera or image capture device, suchas an endoscope, is also commonly introduced into the abdominal cavityto enable the surgeon to view the surgical field and the operation ofthe end effectors during operation. The surgeon is able to view theprocedure in real-time by means of a visual display in communicationwith the image capture device.

Various robotic systems have recently been developed to assist in MISprocedures. Robotic systems can allow for more intuitive hand movementsby maintaining natural eye-hand axis. Robotic systems can also allow formore degrees of freedom in movement by including a “wrist” joint thatcreates a more natural hand-like articulation and allows for access tohard to reach spaces. The instrument's end effector can be articulated(moved) using motors and actuators forming part of a computerized motionsystem. A user (e.g., a surgeon) is able to remotely operate aninstrument's end effector by grasping and manipulating in space one ormore controllers that communicate with an instrument driver coupled tothe surgical instrument. User inputs are processed by a computer systemincorporated into the robotic surgical system and the instrument driverresponds by actuating the motors and actuators of the motion system.Moving the drive cables and/or other mechanical mechanisms manipulatesthe end effector to desired positions and configurations.

Improvements to robotically-enabled medical systems will providephysicians with the ability to perform endoscopic and laparoscopicprocedures more effectively and with improved ease.

SUMMARY OF DISCLOSURE

Various details of the present disclosure are hereinafter summarized toprovide a basic understanding. This summary is not an extensive overviewof the disclosure and is neither intended to identify certain elementsof the disclosure, nor to delineate the scope thereof. Rather, theprimary purpose of this summary is to present some concepts of thedisclosure in a simplified form prior to the more detailed descriptionthat is presented hereinafter.

Embodiments disclosed herein include a robotic surgical tool including adrive housing having a first end, a second end, and a lead screwextending between the first and second ends, a carriage movably mountedto the lead screw at a carriage nut secured to the carriage, anactivating mechanism including a drive gear rotatably mounted to thecarriage and rotatable to actuate the activating mechanism, and atorsion cable extending between the drive gear and a drive inputarranged at the first end, wherein rotating the drive input rotates thetorsion cable and thereby transmits a torsional load along the torsioncable to the drive gear to actuate the activating mechanism. In afurther embodiment, the surgical tool further includes an instrumentdriver arranged at an end of a robotic arm and matable with the drivehousing at the first end, the instrument driver providing a drive outputmatable with the drive input such that rotation of the drive outputcorrespondingly rotates the drive input and thereby rotates the torsioncable to actuate the activating mechanism. In another furtherembodiment, the drive input is a first drive input and the drive outputis a first drive output, the robotic surgical system further comprisinga second drive input arranged at the first end and operatively coupledto the lead screw such that rotation of the second drive inputcorrespondingly rotates the lead screw, and a second drive outputprovided by the instrument driver and matable with the second driveinput such that rotation of the second drive output correspondinglyrotates the second drive input and thereby rotates the lead screw. Inanother further embodiment, the robotic surgical tool further includingan elongate shaft extending from the carriage and penetrating the firstend, an end effector arranged at a distal end of the shaft, and a wristinterposing the shaft and the end effector, wherein actuating theactivating mechanism causes at least one of the following to occur:opening or closing jaws of the end effector, articulating the endeffector at the wrist, and advancing or retracting a knife at the endeffector. In another further embodiment, the end effector is selectedfrom the group consisting of a surgical stapler, a tissue grasper,surgical scissors, an advanced energy vessel sealer, a clip applier, aneedle driver, a babcock including a pair of opposed grasping jaws,bipolar jaws, a suction irrigator, an endoscope, a laparoscope, and anycombination thereof. In another further embodiment, the robotic surgicaltool further includes an elongate shaft extending from the carriage andpenetrating the first end, and an end effector arranged at a distal endof the shaft, wherein the activating mechanism further includes a drivengear rotatably mounted to the carriage and operatively coupled to thedrive gear such that rotation of the drive gear correspondingly rotatesthe driven gear, and a firing rod operatively coupled to the driven gearsuch that rotation of the driven gear causes the firing rod to axiallytranslate along the shaft and cause a knife at the end effector to move.In another further embodiment, the robotic surgical tool furtherincludes tensioning system that includes a tension pulley, a stationarypulley anchored to the drive housing, wherein the torsion cable isrouted through the tension and stationary pulleys, one or more carriagepulleys anchored to the drive housing, and a carriage cable routedthrough the one or more carriage pulleys and extending between thecarriage and the tension pulley, wherein the tension pulley maintainstension in the torsion cable by traveling in an axial direction oppositethe carriage as the carriage traverses the lead screw. In anotherfurther embodiment, the activating mechanism further includes a drivengear provided on an outer circumference of the carriage nut andoperatively coupled to the drive gear such that rotation of the drivegear correspondingly rotates the carriage nut relative to the lead screwand thereby urges the carriage to move axially along the lead screw. Inanother further embodiment, the robotic surgical tool further includingone or more idler gears interposing the drive gear and the driven gearto transfer torque from the drive gear to the driven gear.

Embodiments disclosed herein may further include a method of operating arobotic surgical tool that includes locating the robotic surgical tooladjacent a patient, the robotic surgical tool comprising a drive housinghaving a first end, a second end, and a lead screw extending between thefirst and second ends, a carriage movably mounted to the lead screw at acarriage nut secured to the carriage, an activating mechanism includinga drive gear rotatably mounted to the carriage, and a torsion cableextending between the drive gear and a drive input arranged at the firstend. The method further including rotating the drive input and therebyrotating the torsion cable, and transmitting a torsional load along thetorsion cable to the drive gear as the torsion cable rotates and therebyactuating the activating mechanism. In a further embodiment, aninstrument driver arranged at an end of a robotic arm is mated with thedrive housing at the first end, and the instrument driver provides adrive output matable with the drive input, the method further comprisingrotating the drive output and thereby rotating the drive input and thetorsion cable to actuate the activating mechanism. In another furtherembodiment, the drive input is a first drive input and the drive outputis a first drive output, the method further comprising rotating a secondoutput provided by the instrument driver and thereby rotating a seconddrive input arranged at the first end and operatively coupled to thelead screw, rotating the lead screw as the second drive input rotates,and moving the carriage along the lead screw as the lead screw rotates.In another further embodiment, the surgical tool further includes anelongate shaft extending from the carriage and penetrating the firstend, an end effector arranged at a distal end of the shaft, and a wristinterposing the shaft and the end effector, and wherein actuating theactivating mechanism comprises at least one of the following opening orclosing jaws of the end effector, articulating the end effector at thewrist, and advancing or retracting a knife at the end effector. Inanother further embodiment, the surgical tool further includes anelongate shaft extending from the carriage and penetrating the firstend, an end effector arranged at a distal end of the shaft, the methodfurther comprising rotating the drive gear with the torsion cable, thedrive gear being operatively coupled to a driven gear rotatably mountedto the carriage, and the driven gear being operatively coupled to afiring rod, rotating the driven gear with rotation of the drive gear andthereby causing the firing rod to axially translate along the shaft, andmoving a knife at the end effector as the firing rod axially translates.In another further embodiment, the method further includes maintainingtension in the torsion cable with a tensioning system that includes atension pulley, a stationary pulley anchored to the drive housing,wherein the torsion cable is routed through the tension and stationarypulleys, one or more carriage pulleys anchored to the drive housing, anda carriage cable routed through the one or more carriage pulleys andextending between the carriage and the tension pulley. The methodfurther includes moving the tension pulley in an axial directionopposite the carriage as the carriage traverses the lead screw. Inanother further embodiment, the method further includes feeding thetorsion cable through the tension and stationary pulleys as the tensionpulley moves in the axial direction, and feeding the carriage cablethrough the one or more carriage pulleys as the carriage traverses thelead screw. In another further embodiment, the activating mechanismfurther includes a driven gear provided on an outer circumference of thecarriage nut and operatively coupled to the drive gear, the methodfurther comprising rotating the drive gear with the torsion cable andthereby rotating the driven gear, and rotating the carriage nut as thedriven gear rotates and thereby urging the carriage to move axiallyalong the lead screw. In another further embodiment, the method furtherincludes one or more idler gears interposing the drive gear and thedriven gear to transfer torque from the drive gear to the driven gear.

Embodiments disclosed herein may further include another roboticsurgical system that includes a drive housing having a first end, asecond end, and a lead screw extending between the first and secondends, a carriage movably mounted to the lead screw at a carriage nutsecured to the carriage, an elongate shaft extending from the carriageand penetrating the first end, and an end effector arranged at a distalend of the shaft, a drive gear rotatably mounted to the carriage, adriven gear rotatably mounted to the carriage and operatively coupled tothe drive gear such that rotation of the drive gear correspondinglyrotates the driven gear, and a firing rod operatively coupled to thedriven gear such that rotation of the driven gear causes the firing rodto axially translate along the shaft and cause a knife at the endeffector to move. In a further embodiment, the robotic surgical toolfurther includes a tensioning system that includes a tension pulley, astationary pulley anchored to the drive housing, wherein the torsioncable is routed through the tension and stationary pulleys, one or morecarriage pulleys anchored to the drive housing, and a carriage cablerouted through the one or more carriage pulleys and extending betweenthe carriage and the tension pulley, wherein the tension pulleymaintains tension in the torsion cable by traveling in an axialdirection opposite the carriage as the carriage traverses the leadscrew.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosed aspects will hereinafter be described in conjunction withthe appended drawings, provided to illustrate and not to limit thedisclosed aspects, wherein like designations denote like elements.

FIG. 1 illustrates an embodiment of a cart-based robotic system arrangedfor diagnostic and/or therapeutic bronchoscopy procedure(s).

FIG. 2 depicts further aspects of the robotic system of FIG. 1.

FIG. 3A illustrates an embodiment of the robotic system of FIG. 1arranged for ureteroscopy.

FIG. 3B illustrates an embodiment of the robotic system of FIG. 1arranged for a vascular procedure.

FIG. 4 illustrates an embodiment of a table-based robotic systemarranged for a bronchoscopy procedure.

FIG. 5 provides an alternative view of the robotic system of FIG. 4.

FIG. 6 illustrates an example system configured to stow robotic arm(s).

FIG. 7A illustrates an embodiment of a table-based robotic systemconfigured for a ureteroscopy procedure.

FIG. 7B illustrates an embodiment of a table-based robotic systemconfigured for a laparoscopic procedure.

FIG. 7C illustrates an embodiment of the table-based robotic system ofFIGS. 4-7B with pitch or tilt adjustment.

FIG. 8 provides a detailed illustration of the interface between thetable and the column of the table-based robotic system of FIGS. 4-7.

FIG. 9A illustrates an alternative embodiment of a table-based roboticsystem.

FIG. 9B illustrates an end view of the table-based robotic system ofFIG. 9A.

FIG. 9C illustrates an end view of a table-based robotic system withrobotic arms attached thereto.

FIG. 10 illustrates an exemplary instrument driver.

FIG. 11 illustrates an exemplary medical instrument with a pairedinstrument driver.

FIG. 12 illustrates an alternative design for an instrument driver andinstrument where the axes of the drive units are parallel to the axis ofthe elongated shaft of the instrument.

FIG. 13 illustrates an instrument having an instrument-based insertionarchitecture.

FIG. 14 illustrates an exemplary controller.

FIG. 15 depicts a block diagram illustrating a localization system thatestimates a location of one or more elements of the robotic systems ofFIGS. 1-7C, such as the location of the instrument of FIGS. 11-13, inaccordance to an example embodiment.

FIG. 16 is an isometric side view of an example surgical tool that mayincorporate some or all of the principles of the present disclosure.

FIG. 17A is an isometric view of the surgical tool of FIG. 16 releasablycoupled to an example instrument driver, according to one or moreembodiments.

FIG. 17B provides separated isometric end views of the instrument driverand the surgical tool of FIG. 17A.

FIGS. 18A and 18B are enlarged isometric and side views, respectively,of the carriage and the second activating mechanism of FIG. 16.

FIG. 18C is an isometric, cross-sectional side view of the secondactivating mechanism of FIG. 16, according to one or more embodiments.

FIG. 19 is an enlarged view of the end effector of FIG. 16 and anexposed view of the wrist of FIG. 16, according to one or moreembodiments.

FIG. 20 is an enlarged cross-sectional side view of another embodimentof the second activating mechanism of FIGS. 18A-18C.

FIGS. 21A and 21B are enlarged isometric top and bottom views,respectively, of an example carriage, according to one or moreembodiments.

FIGS. 22A and 22B are isometric top and bottom views, respectively, of aportion of the activation mechanism of FIGS. 21A-21B, according to oneor more embodiments.

FIG. 23 is a cross-sectional side view of the carriage of FIGS. 21A-21B.

FIG. 24 is another enlarged isometric view of the carriage of FIG. 16.

FIG. 25 is an enlarged view of the proximal end of the carriage and thethird activating mechanism of FIG. 24.

FIG. 26 is an isometric, cross-sectional side view of the thirdactivating mechanism of FIGS. 24 and 25, according to one or moreembodiments.

FIG. 27 is an enlarged cross-sectional view of the end effector of FIG.16, according to one or more embodiments.

FIG. 28A is an enlarged isometric view of another embodiment of thecarriage of FIG. 16.

FIG. 28B is an enlarged isometric view of the first activating mechanismof FIG. 28A, according to one or more embodiments.

FIG. 28C is an isometric, cross-sectional side view of the firstactivating mechanism of FIGS. 28A-28B.

FIG. 29 is an enlarged view of the end effector and the wrist of FIG.16, according to one or more embodiments.

FIG. 30A is another enlarged isometric top view of the carriage of FIGS.21A and 21B, according to one or more additional embodiments.

FIG. 30B is an enlarged view of the activating mechanism of FIG. 30A,according to one or more embodiments.

FIG. 30C is a cross-sectional side view of a portion of the carriage ofFIGS. 30A-30B and the activation mechanism of FIGS. 30A-30B.

FIG. 31 is an isometric view of an example embodiment of the closurebarrel of FIGS. 30A-30C, according to one or more embodiments.

FIG. 32 is another enlarged isometric view of the carriage of FIG. 16.

FIGS. 33A and 33B are isometric end views of the carriage nut of FIGS.16 and 32, according to one or more example embodiments.

FIGS. 34A and 34B are isometric views of the first and second ends,respectively, of the handle of FIG. 16, according to one or moreembodiments.

FIG. 35 is another example of the handle of FIG. 16, according to one ormore additional embodiments.

FIG. 36A is a perspective view of the instrument driver of FIGS. 17A and17B, and FIG. 36B is an isometric view of the surgical tool of FIG. 16releasably coupled to the instrument driver, according to one or moreembodiments.

FIG. 37A is a schematic diagram of an example embodiment of theinstrument driver of FIGS. 36A-36B, according to one or moreembodiments.

FIG. 37B is a cross-sectional view of the instrument driver of FIG. 37A,according to one or more embodiments.

FIG. 37C illustrates a partially exploded, perspective view of theinternal mechanical and electrical components of the instrument driverof FIG. 37A, according to one or more embodiments.

FIG. 37D is a partially exploded, perspective view of the internalelectrical components of the instrument driver of FIG. 37A, according toone or more embodiments.

FIG. 38 is a zoomed-in, perspective view of various electricalcomponents of the instrument driver of FIG. 37A, according to one ormore embodiments.

FIGS. 39A and 39B are partial cross-sectional side views of anotherexample of the handle of FIG. 16, according to one or more additionalembodiments.

FIGS. 40A and 40B are partial cross-sectional side views of anotherexample of the handle of FIG. 16, according to one or more additionalembodiments.

FIG. 40C is an alternative embodiment of the drive housing of FIGS.40A-40B.

FIGS. 41A-41C are partial cross-sectional side views of alternativeembodiments of the drive housing of FIG. 16, according to one or moreadditional embodiments.

DETAILED DESCRIPTION 1. Overview.

Aspects of the present disclosure may be integrated into arobotically-enabled medical system capable of performing a variety ofmedical procedures, including both minimally invasive (e.g.,laparoscopy) and non-invasive (e.g., endoscopy) procedures. Amongendoscopy procedures, the system may be capable of performingbronchoscopy, ureteroscopy, gastroscopy, etc.

In addition to performing the breadth of procedures, the system mayprovide additional benefits, such as enhanced imaging and guidance toassist the physician. Additionally, the system may provide the physicianwith the ability to perform the procedure from an ergonomic positionwithout the need for awkward arm motions and positions. Still further,the system may provide the physician with the ability to perform theprocedure with improved ease of use such that one or more of theinstruments of the system can be controlled by a single user.

Various embodiments will be described below in conjunction with thedrawings for purposes of illustration. It should be appreciated thatmany other implementations of the disclosed concepts are possible, andvarious advantages can be achieved with the disclosed implementations.Headings are included herein for reference and to aid in locatingvarious sections. These headings are not intended to limit the scope ofthe concepts described with respect thereto. Such concepts may haveapplicability throughout the entire specification.

A. Robotic System—Cart.

The robotically-enabled medical system may be configured in a variety ofways depending on the particular procedure. FIG. 1 illustrates anembodiment of a cart-based robotically-enabled system 100 arranged for adiagnostic and/or therapeutic bronchoscopy procedure. For a bronchoscopyprocedure, the robotic system 100 may include a cart 102 having one ormore robotic arms 104 (three shown) to deliver a medical instrument(alternately referred to as a “surgical tool”), such as a steerableendoscope 106 (e.g., a procedure-specific bronchoscope forbronchoscopy), to a natural orifice access point (i.e., the mouth of thepatient) to deliver diagnostic and/or therapeutic tools. As shown, thecart 102 may be positioned proximate to the patient's upper torso inorder to provide access to the access point. Similarly, the robotic arms104 may be actuated to position the bronchoscope relative to the accesspoint. The arrangement in FIG. 1 may also be utilized when performing agastro-intestinal (GI) procedure with a gastroscope, a specializedendoscope for GI procedures.

Once the cart 102 is properly positioned adjacent the patient, therobotic arms 104 are operated to insert the steerable endoscope 106 intothe patient robotically, manually, or a combination thereof. Thesteerable endoscope 106 may comprise at least two telescoping parts,such as an inner leader portion and an outer sheath portion, where eachportion is coupled to a separate instrument driver of a set ofinstrument drivers 108. As illustrated, each instrument driver 108 iscoupled to the distal end of a corresponding one of the robotic arms104. This linear arrangement of the instrument drivers 108, whichfacilitates coaxially aligning the leader portion with the sheathportion, creates a “virtual rail” 110 that may be repositioned in spaceby manipulating the robotic arms 104 into different angles and/orpositions. Translation of the instrument drivers 108 along the virtualrail 110 telescopes the inner leader portion relative to the outersheath portion, thus effectively advancing or retracting the endoscope106 relative to the patient.

As illustrated, the virtual rail 110 (and other virtual rails describedherein) is depicted in the drawings using dashed lines, thus notconstituting any physical structure of the system 100. The angle of thevirtual rail 110 may be adjusted, translated, and pivoted based onclinical application or physician preference. For example, inbronchoscopy, the angle and position of the virtual rail 110 as shownrepresents a compromise between providing physician access to theendoscope 106 while minimizing friction that results from bending theendoscope 106 into the patient's mouth.

After insertion into the patient's mouth, the endoscope 106 may bedirected down the patient's trachea and lungs using precise commandsfrom the robotic system 100 until reaching a target destination oroperative site. In order to enhance navigation through the patient'slung network and/or reach the desired target, the endoscope 106 may bemanipulated to telescopically extend the inner leader portion from theouter sheath portion to obtain enhanced articulation and greater bendradius. The use of separate instrument drivers 108 also allows theleader portion and sheath portion to be driven independent of eachother.

For example, the endoscope 106 may be directed to deliver a biopsyneedle to a target, such as, for example, a lesion or nodule within thelungs of a patient. The needle may be deployed down a working channelthat runs the length of the endoscope 106 to obtain a tissue sample tobe analyzed by a pathologist. Depending on the pathology results,additional tools may be deployed down the working channel of theendoscope for additional biopsies.

After identifying a tissue sample to be malignant, the endoscope 106 mayendoscopically deliver tools to resect the potentially cancerous tissue.In some instances, diagnostic and therapeutic treatments can bedelivered in separate procedures. In those circumstances, the endoscope106 may also be used to deliver a fiducial marker to “mark” the locationof a target nodule as well. In other instances, diagnostic andtherapeutic treatments may be delivered during the same procedure.

The system 100 may also include a movable tower 112, which may beconnected via support cables to the cart 102 to provide support forcontrols, electronics, fluidics, optics, sensors, and/or power to thecart 102. Placing such functionality in the tower 112 allows for asmaller form factor cart 102 that may be more easily adjusted and/orre-positioned by an operating physician and his/her staff. Additionally,the division of functionality between the cart/table and the supporttower 112 reduces operating room clutter and facilitates improvingclinical workflow. While the cart 102 may be positioned close to thepatient, the tower 112 may alternatively be stowed in a remote locationto stay out of the way during a procedure.

In support of the robotic systems described above, the tower 112 mayinclude component(s) of a computer-based control system that storescomputer program instructions, for example, within a non-transitorycomputer-readable storage medium such as a persistent magnetic storagedrive, solid state drive, etc. The execution of those instructions,whether the execution occurs in the tower 112 or the cart 102, maycontrol the entire system or sub-system(s) thereof. For example, whenexecuted by a processor of the computer system, the instructions maycause the components of the robotics system to actuate the relevantcarriages and arm mounts, actuate the robotics arms, and control themedical instruments. For example, in response to receiving the controlsignal, motors in the joints of the robotic arms 104 may position thearms into a certain posture or angular orientation.

The tower 112 may also include one or more of a pump, flow meter, valvecontrol, and/or fluid access in order to provide controlled irrigationand aspiration capabilities to the system 100 that may be deployedthrough the endoscope 106. These components may also be controlled usingthe computer system of the tower 112. In some embodiments, irrigationand aspiration capabilities may be delivered directly to the endoscope106 through separate cable(s).

The tower 112 may include a voltage and surge protector designed toprovide filtered and protected electrical power to the cart 102, therebyavoiding placement of a power transformer and other auxiliary powercomponents in the cart 102, resulting in a smaller, more movable cart102.

The tower 112 may also include support equipment for sensors deployedthroughout the robotic system 100. For example, the tower 112 mayinclude opto-electronics equipment for detecting, receiving, andprocessing data received from optical sensors or cameras throughout therobotic system 100. In combination with the control system, suchopto-electronics equipment may be used to generate real-time images fordisplay in any number of consoles deployed throughout the system,including in the tower 112. Similarly, the tower 112 may also include anelectronic subsystem for receiving and processing signals received fromdeployed electromagnetic (EM) sensors. The tower 112 may also be used tohouse and position an EM field generator for detection by EM sensors inor on the medical instrument.

The tower 112 may also include a console 114 in addition to otherconsoles available in the rest of the system, e.g., a console mounted tothe cart 102. The console 114 may include a user interface and a displayscreen (e.g., a touchscreen) for the physician operator. Consoles in thesystem 100 are generally designed to provide both robotic controls aswell as pre-operative and real-time information of the procedure, suchas navigational and localization information of the endoscope 106. Whenthe console 114 is not the only console available to the physician, itmay be used by a second operator, such as a nurse, to monitor the healthor vitals of the patient and the operation of system, as well as provideprocedure-specific data, such as navigational and localizationinformation. In other embodiments, the console 114 may be housed in abody separate from the tower 112.

The tower 112 may be coupled to the cart 102 and endoscope 106 throughone or more cables 116 connections. In some embodiments, supportfunctionality from the tower 112 may be provided through a single cable116 extending to the cart 102, thus simplifying and de-cluttering theoperating room. In other embodiments, specific functionality may becoupled in separate cabling and connections. For example, while powermay be provided through a single power cable to the cart 102, supportfor controls, optics, fluidics, and/or navigation may be providedthrough one or more separate cables.

FIG. 2 provides a detailed illustration of an embodiment of the cart 102from the cart-based robotically-enabled system 100 of FIG. 1. The cart102 generally includes an elongated support structure 202 (also referredto as a “column”), a cart base 204, and a console 206 at the top of thecolumn 202. The column 202 may include one or more carriages, such as acarriage 208 (alternatively “arm support”) for supporting the deploymentof the robotic arms 104. The carriage 208 may include individuallyconfigurable arm mounts that rotate along a perpendicular axis to adjustthe base 214 of the robotic arms 104 for better positioning relative tothe patient. The carriage 208 also includes a carriage interface 210that allows the carriage 208 to vertically translate along the column202.

The carriage interface 210 is connected to the column 202 through slots,such as slot 212, that are positioned on opposite sides of the column202 to guide the vertical translation of the carriage 208. The slot 212contains a vertical translation interface to position and hold thecarriage 208 at various vertical heights relative to the cart base 204.Vertical translation of the carriage 208 allows the cart 102 to adjustthe reach of the robotic arms 104 to meet a variety of table heights,patient sizes, and physician preferences. Similarly, the individuallyconfigurable arm mounts on the carriage 208 allow a base 214 of therobotic arms 104 to be angled in a variety of configurations.

In some embodiments, the slot 212 may be supplemented with slot covers(not shown) that are flush and parallel to the slot surface to preventdirt and fluid ingress into the internal chambers of the column 202 andthe vertical translation interface as the carriage 208 verticallytranslates. The slot covers may be deployed through pairs of springspools positioned near the vertical top and bottom of the slot 212. Thecovers are coiled within the spools until deployed to extend and retractfrom their coiled state as the carriage 208 vertically translates up anddown. The spring-loading of the spools provides force to retract thecover into a spool when carriage 208 translates towards the spool, whilealso maintaining a tight seal when the carriage 208 translates away fromthe spool. The covers may be connected to the carriage 208 using, forexample, brackets in the carriage interface 210 to ensure properextension and retraction of the cover as the carriage 208 translates.

The column 202 may internally comprise mechanisms, such as gears andmotors, that are designed to use a vertically aligned lead screw totranslate the carriage 208 in a mechanized fashion in response tocontrol signals generated in response to user inputs, e.g., inputs fromthe console 206.

The robotic arms 104 may generally comprise robotic arm bases 214 andend effectors 216 (three shown), separated by a series of linkages 218connected by a corresponding series of joints 220, each joint 220including an independent actuator, and each actuator including anindependently controllable motor. Each independently controllable joint220 represents an independent degree of freedom available to thecorresponding robotic arm 104. In the illustrated embodiment, each arm104 has seven joints 220, thus providing seven degrees of freedom. Amultitude of joints 220 result in a multitude of degrees of freedom,allowing for “redundant” degrees of freedom. Redundant degrees offreedom allow the robotic arms 104 to position their respective endeffectors 216 at a specific position, orientation, and trajectory inspace using different linkage positions and joint angles. This allowsfor the system 100 to position and direct a medical instrument from adesired point in space while allowing the physician to move the armjoints 220 into a clinically advantageous position away from the patientto create greater access, while avoiding arm collisions.

The cart base 204 balances the weight of the column 202, carriage 208,and arms 104 over the floor. Accordingly, the cart base 204 housesheavier components, such as electronics, motors, power supply, as wellas components that either enable movement and/or immobilize the cart.For example, the cart base 204 includes rolling casters 222 that allowfor the cart to easily move around the room prior to a procedure. Afterreaching an appropriate position, the casters 222 may be immobilizedusing wheel locks to hold the cart 102 in place during the procedure.

Positioned at the vertical end of the column 202, the console 206 allowsfor both a user interface for receiving user input and a display screen(or a dual-purpose device such as, for example, a touchscreen 224) toprovide the physician user with both pre-operative and intra-operativedata. Potential pre-operative data on the touchscreen 224 may includepre-operative plans, navigation and mapping data derived frompre-operative computerized tomography (CT) scans, and/or notes frompre-operative patient interviews. Intra-operative data on thetouchscreen 224 may include optical information provided from the tool,sensor and coordinate information from sensors, as well as vital patientstatistics, such as respiration, heart rate, and/or pulse. The console206 may be positioned and tilted to allow a physician to access theconsole from the side of the column 202 opposite carriage 208. From thisposition, the physician may view the console 206, the robotic arms 104,and the patient while operating the console 206 from behind the cart102. As shown, the console 206 also includes a handle 226 to assist withmaneuvering and stabilizing cart 102.

FIG. 3A illustrates an embodiment of the system 100 of FIG. 1 arrangedfor ureteroscopy. In a ureteroscopic procedure, the cart 102 may bepositioned to deliver a ureteroscope 302, a procedure-specific endoscopedesigned to traverse a patient's urethra and ureter, to the lowerabdominal area of the patient. In ureteroscopy, it may be desirable forthe ureteroscope 302 to be directly aligned with the patient's urethrato reduce friction and forces on the sensitive anatomy. As shown, thecart 102 may be aligned at the foot of the table to allow the roboticarms 104 to position the ureteroscope 302 for direct linear access tothe patient's urethra. From the foot of the table, the robotic arms 104may insert the ureteroscope 302 along a virtual rail 304 directly intothe patient's lower abdomen through the urethra.

After insertion into the urethra, using similar control techniques as inbronchoscopy, the ureteroscope 302 may be navigated into the bladder,ureters, and/or kidneys for diagnostic and/or therapeutic applications.For example, the ureteroscope 302 may be directed into the ureter andkidneys to break up kidney stone build-up using a laser or ultrasoniclithotripsy device deployed down a working channel of the ureteroscope302. After lithotripsy is complete, the resulting stone fragments may beremoved using baskets deployed down the working channel of theureteroscope 302.

FIG. 3B illustrates another embodiment of the system 100 of FIG. 1arranged for a vascular procedure. In a vascular procedure, the system100 may be configured such that the cart 102 may deliver a medicalinstrument 306, such as a steerable catheter, to an access point in thefemoral artery in the patient's leg. The femoral artery presents both alarger diameter for navigation as well as a relatively less circuitousand tortuous path to the patient's heart, which simplifies navigation.As in a ureteroscopic procedure, the cart 102 may be positioned towardsthe patient's legs and lower abdomen to allow the robotic arms 104 toprovide a virtual rail 308 with direct linear access to the femoralartery access point in the patient's thigh/hip region. After insertioninto the artery, the medical instrument 306 may be directed and advancedby translating the instrument drivers 108. Alternatively, the cart 102may be positioned around the patient's upper abdomen in order to reachalternative vascular access points, such as, for example, the carotidand brachial arteries near the patient's shoulder and wrist.

B. Robotic System—Table.

Embodiments of the robotically-enabled medical system may alsoincorporate the patient's table. Incorporation of the table reduces theamount of capital equipment within the operating room by removing thecart, which allows greater access to the patient. FIG. 4 illustrates anembodiment of such a robotically-enabled system 400 arranged for abronchoscopy procedure. As illustrated, the system 400 includes asupport structure or column 402 for supporting platform 404 (shown as a“table” or “bed”) over the floor. Much like in the cart-based systems,the end effectors of the robotic arms 406 of the system 400 compriseinstrument drivers 408 that are designed to manipulate an elongatedmedical instrument, such as a bronchoscope 410, through or along avirtual rail 412 formed from the linear alignment of the instrumentdrivers 408. In practice, a C-arm for providing fluoroscopic imaging maybe positioned over the patient's upper abdominal area by placing theemitter and detector around the table 404.

FIG. 5 provides an alternative view of the system 400 without thepatient and medical instrument for discussion purposes. As shown, thecolumn 402 may include one or more carriages 502 shown as ring-shaped inthe system 400, from which the one or more robotic arms 406 may bebased. The carriages 502 may translate along a vertical column interface504 that runs the length (height) of the column 402 to provide differentvantage points from which the robotic arms 406 may be positioned toreach the patient. The carriage(s) 502 may rotate around the column 402using a mechanical motor positioned within the column 402 to allow therobotic arms 406 to have access to multiples sides of the table 404,such as, for example, both sides of the patient. In embodiments withmultiple carriages 502, the carriages 502 may be individually positionedon the column 402 and may translate and/or rotate independent of theother carriages 502. While carriages 502 need not surround the column402 or even be circular, the ring-shape as shown facilitates rotation ofthe carriages 502 around the column 402 while maintaining structuralbalance. Rotation and translation of the carriages 502 allows the system400 to align medical instruments, such as endoscopes and laparoscopes,into different access points on the patient.

In other embodiments (discussed in greater detail below with respect toFIG. 9A), the system 400 can include a patient table or bed withadjustable arm supports in the form of bars or rails extending alongsideit. One or more robotic arms 406 (e.g., via a shoulder with an elbowjoint) can be attached to the adjustable arm supports, which can bevertically adjusted. By providing vertical adjustment, the robotic arms406 are advantageously capable of being stowed compactly beneath thepatient table or bed, and subsequently raised during a procedure.

The arms 406 may be mounted on the carriages 502 through a set of armmounts 506 comprising a series of joints that may individually rotateand/or telescopically extend to provide additional configurability tothe robotic arms 406. Additionally, the arm mounts 506 may be positionedon the carriages 502 such that when the carriages 502 are appropriatelyrotated, the arm mounts 506 may be positioned on either the same side ofthe table 404 (as shown in FIG. 5), on opposite sides of table 404 (asshown in FIG. 7B), or on adjacent sides of the table 404 (not shown).

The column 402 structurally provides support for the table 404, and apath for vertical translation of the carriages 502. Internally, thecolumn 402 may be equipped with lead screws for guiding verticaltranslation of the carriages, and motors to mechanize the translation ofsaid carriages based the lead screws. The column 402 may also conveypower and control signals to the carriage 502 and robotic arms 406mounted thereon.

A table base 508 serves a similar function as the cart base 204 of thecart 102 shown in FIG. 2, housing heavier components to balance thetable/bed 404, the column 402, the carriages 502, and the robotic arms406. The table base 508 may also incorporate rigid casters to providestability during procedures. Deployed from the bottom of the table base508, the casters may extend in opposite directions on both sides of thebase 508 and retract when the system 400 needs to be moved.

In some embodiments, the system 400 may also include a tower (not shown)that divides the functionality of system 400 between table and tower toreduce the form factor and bulk of the table 404. As in earlierdisclosed embodiments, the tower may provide a variety of supportfunctionalities to the table 404, such as processing, computing, andcontrol capabilities, power, fluidics, and/or optical and sensorprocessing. The tower may also be movable to be positioned away from thepatient to improve physician access and de-clutter the operating room.Additionally, placing components in the tower allows for more storagespace in the table base 508 for potential stowage of the robotic arms406. The tower may also include a master controller or console thatprovides both a user interface for user input, such as keyboard and/orpendant, as well as a display screen (or touchscreen) for pre-operativeand intra-operative information, such as real-time imaging, navigation,and tracking information. In some embodiments, the tower may alsocontain holders for gas tanks to be used for insufflation.

In some embodiments, a table base may stow and store the robotic armswhen not in use. FIG. 6 illustrates an embodiment of the system 400 thatis configured to stow robotic arms in an embodiment of the table-basedsystem. In the system 400, one or more carriages 602 (one shown) may bevertically translated into a base 604 to stow one or more robotic arms606, one or more arm mounts 608, and the carriages 602 within the base604. Base covers 610 may be translated and retracted open to deploy thecarriages 602, the arm mounts 608, and the arms 606 around the column612, and closed to stow and protect them when not in use. The basecovers 610 may be sealed with a membrane 614 along the edges of itsopening to prevent dirt and fluid ingress when closed.

FIG. 7A illustrates an embodiment of the robotically-enabled table-basedsystem 400 configured for a ureteroscopy procedure. In ureteroscopy, thetable 404 may include a swivel portion 702 for positioning a patientoff-angle from the column 402 and the table base 508. The swivel portion702 may rotate or pivot around a pivot point (e.g., located below thepatient's head) in order to position the bottom portion of the swivelportion 702 away from the column 402. For example, the pivoting of theswivel portion 702 allows a C-arm (not shown) to be positioned over thepatient's lower abdomen without competing for space with the column (notshown) below table 404. By rotating the carriage (not shown) around thecolumn 402, the robotic arms 406 may directly insert a ureteroscope 704along a virtual rail 706 into the patient's groin area to reach theurethra. In ureteroscopy, stirrups 708 may also be fixed to the swivelportion 702 of the table 404 to support the position of the patient'slegs during the procedure and allow clear access to the patient's groinarea.

FIG. 7B illustrates an embodiment of the system 400 configured for alaparoscopic procedure. In a laparoscopic procedure, through smallincision(s) in the patient's abdominal wall, minimally invasiveinstruments may be inserted into the patient's anatomy. In someembodiments, the minimally invasive instruments comprise an elongatedrigid member, such as a shaft, which is used to access anatomy withinthe patient. After inflation of the patient's abdominal cavity, theinstruments may be directed to perform surgical or medical tasks, suchas grasping, cutting, ablating, suturing, etc. In some embodiments, theinstruments can comprise a scope, such as a laparoscope. As shown inFIG. 7B, the carriages 502 of the system 400 may be rotated andvertically adjusted to position pairs of the robotic arms 406 onopposite sides of the table 404, such that an instrument 710 may bepositioned using the arm mounts 506 to be passed through minimalincisions on both sides of the patient to reach his/her abdominalcavity.

To accommodate laparoscopic procedures, the system 400 may also tilt theplatform to a desired angle. FIG. 7C illustrates an embodiment of thesystem 400 with pitch or tilt adjustment. As shown in FIG. 7C, thesystem 400 may accommodate tilt of the table 404 to position one portionof the table 404 at a greater distance from the floor than the other.Additionally, the arm mounts 506 may rotate to match the tilt such thatthe arms 406 maintain the same planar relationship with table 404. Toaccommodate steeper angles, the column 402 may also include telescopingportions 712 that allow vertical extension of the column 402 to keep thetable 404 from touching the floor or colliding with the base 508.

FIG. 8 provides a detailed illustration of the interface between thetable 404 and the column 402. Pitch rotation mechanism 802 may beconfigured to alter the pitch angle of the table 404 relative to thecolumn 402 in multiple degrees of freedom. The pitch rotation mechanism802 may be enabled by the positioning of orthogonal axes A and B at thecolumn-table interface, each axis actuated by a separate motor 804 a and804 b responsive to an electrical pitch angle command. Rotation alongone screw 806 a would enable tilt adjustments in one axis A, whilerotation along another screw 806 b would enable tilt adjustments alongthe other axis B. In some embodiments, a ball joint can be used to alterthe pitch angle of the table 404 relative to the column 402 in multipledegrees of freedom.

For example, pitch adjustments are particularly useful when trying toposition the table in a Trendelenburg position, i.e., position thepatient's lower abdomen at a higher position from the floor than thepatient's lower abdomen, for lower abdominal surgery. The Trendelenburgposition causes the patient's internal organs to slide towards his/herupper abdomen through the force of gravity, clearing out the abdominalcavity for minimally invasive tools to enter and perform lower abdominalsurgical or medical procedures, such as laparoscopic prostatectomy.

FIGS. 9A and 9B illustrate isometric and end views, respectively, of analternative embodiment of a table-based surgical robotics system 900.The surgical robotics system 900 includes one or more adjustable armsupports 902 that can be configured to support one or more robotic arms(see, for example, FIG. 9C) relative to a table 904. In the illustratedembodiment, a single adjustable arm support 902 is shown, though anadditional arm support can be provided on an opposite side of the table904. The adjustable arm support 902 can be configured so that it canmove relative to the table 904 to adjust and/or vary the position of theadjustable arm support 902 and/or any robotic arms mounted theretorelative to the table 904. For example, the adjustable arm support 902may be adjusted in one or more degrees of freedom relative to the table904. The adjustable arm support 902 provides high versatility to thesystem 900, including the ability to easily stow the one or moreadjustable arm supports 902 and any robotics arms attached theretobeneath the table 904. The adjustable arm support 902 can be elevatedfrom the stowed position to a position below an upper surface of thetable 904. In other embodiments, the adjustable arm support 902 can beelevated from the stowed position to a position above an upper surfaceof the table 904.

The adjustable arm support 902 can provide several degrees of freedom,including lift, lateral translation, tilt, etc. In the illustratedembodiment of FIGS. 9A and 9B, the arm support 902 is configured withfour degrees of freedom, which are illustrated with arrows in FIG. 9A. Afirst degree of freedom allows for adjustment of the adjustable armsupport 902 in the z-direction (“Z-lift”). For example, the adjustablearm support 902 can include a carriage 906 configured to move up or downalong or relative to a column 908 supporting the table 904. A seconddegree of freedom can allow the adjustable arm support 902 to tilt. Forexample, the adjustable arm support 902 can include a rotary joint,which can allow the adjustable arm support 902 to be aligned with thebed in a Trendelenburg position. A third degree of freedom can allow theadjustable arm support 902 to “pivot up,” which can be used to adjust adistance between a side of the table 904 and the adjustable arm support902. A fourth degree of freedom can permit translation of the adjustablearm support 902 along a longitudinal length of the table.

The surgical robotics system 900 in FIGS. 9A and 9B can comprise a table904 supported by a column 908 that is mounted to a base 910. The base910 and the column 908 support the table 904 relative to a supportsurface. A floor axis 912 and a support axis 914 are shown in FIG. 9B.

The adjustable arm support 902 can be mounted to the column 908. Inother embodiments, the arm support 902 can be mounted to the table 904or the base 910. The adjustable arm support 902 can include a carriage906, a bar or rail connector 916 and a bar or rail 918. In someembodiments, one or more robotic arms mounted to the rail 918 cantranslate and move relative to one another.

The carriage 906 can be attached to the column 908 by a first joint 920,which allows the carriage 906 to move relative to the column 908 (e.g.,such as up and down a first or vertical axis 922). The first joint 920can provide the first degree of freedom (“Z-lift”) to the adjustable armsupport 902. The adjustable arm support 902 can include a second joint924, which provides the second degree of freedom (tilt) for theadjustable arm support 902. The adjustable arm support 902 can include athird joint 926, which can provide the third degree of freedom (“pivotup”) for the adjustable arm support 902. An additional joint 928 (shownin FIG. 9B) can be provided that mechanically constrains the third joint926 to maintain an orientation of the rail 918 as the rail connector 916is rotated about a third axis 930. The adjustable arm support 902 caninclude a fourth joint 932, which can provide a fourth degree of freedom(translation) for the adjustable arm support 902 along a fourth axis934.

FIG. 9C illustrates an end view of the surgical robotics system 900 withtwo adjustable arm supports 902 a and 902 b mounted on opposite sides ofthe table 904. A first robotic arm 936 a is attached to the first bar orrail 918 a of the first adjustable arm support 902 a. The first roboticarm 936 a includes a base 938 a attached to the first rail 918 a. Thedistal end of the first robotic arm 936 a includes an instrument drivemechanism or input 940 a that can attach to one or more robotic medicalinstruments or tools. Similarly, the second robotic arm 936 b includes abase 938 a attached to the second rail 918 b. The distal end of thesecond robotic arm 936 b includes an instrument drive mechanism or input940 b configured to attach to one or more robotic medical instruments ortools.

In some embodiments, one or more of the robotic arms 936 a,b comprisesan arm with seven or more degrees of freedom. In some embodiments, oneor more of the robotic arms 936 a,b can include eight degrees offreedom, including an insertion axis (1-degree of freedom includinginsertion), a wrist (3-degrees of freedom including wrist pitch, yaw androll), an elbow (1-degree of freedom including elbow pitch), a shoulder(2-degrees of freedom including shoulder pitch and yaw), and base 938a,b (1-degree of freedom including translation). In some embodiments,the insertion degree of freedom can be provided by the robotic arm 936a,b, while in other embodiments, the instrument itself providesinsertion via an instrument-based insertion architecture.

C. Instrument Driver & Interface.

The end effectors of a system's robotic arms comprise (i) an instrumentdriver (alternatively referred to as “tool driver,” “instrument drivemechanism,” “instrument device manipulator,” and “drive input”) thatincorporate electro-mechanical means for actuating the medicalinstrument, and (ii) a removable or detachable medical instrument, whichmay be devoid of any electro-mechanical components, such as motors. Thisdichotomy may be driven by the need to sterilize medical instrumentsused in medical procedures, and the inability to adequately sterilizeexpensive capital equipment due to their intricate mechanical assembliesand sensitive electronics. Accordingly, the medical instruments may bedesigned to be detached, removed, and interchanged from the instrumentdriver (and thus the system) for individual sterilization or disposal bythe physician or the physician's staff. In contrast, the instrumentdrivers need not be changed or sterilized, and may be draped forprotection.

FIG. 10 illustrates an example instrument driver 1000, according to oneor more embodiments. Positioned at the distal end of a robotic arm, theinstrument driver 1000 comprises of one or more drive outputs 1002arranged with parallel axes to provide controlled torque to a medicalinstrument via corresponding drive shafts 1004. Each drive output 1002comprises an individual drive shaft 1004 for interacting with theinstrument, a gear head 1006 for converting the motor shaft rotation toa desired torque, a motor 1008 for generating the drive torque, and anencoder 1010 to measure the speed of the motor shaft and providefeedback to control circuitry 1012, which can also be used for receivingcontrol signals and actuating the drive output 1002. Each drive output1002 being independent controlled and motorized, the instrument driver1000 may provide multiple (at least two shown in FIG. 10) independentdrive outputs to the medical instrument. In operation, the controlcircuitry 1012 receives a control signal, transmits a motor signal tothe motor 1008, compares the resulting motor speed as measured by theencoder 1010 with the desired speed, and modulates the motor signal togenerate the desired torque.

For procedures that require a sterile environment, the robotic systemmay incorporate a drive interface, such as a sterile adapter connectedto a sterile drape, that sits between the instrument driver and themedical instrument. The chief purpose of the sterile adapter is totransfer angular motion from the drive shafts of the instrument driverto the drive inputs of the instrument while maintaining physicalseparation, and thus sterility, between the drive shafts and driveinputs. Accordingly, an example sterile adapter may comprise of a seriesof rotational inputs and outputs intended to be mated with the driveshafts of the instrument driver and drive inputs on the instrument.Connected to the sterile adapter, the sterile drape, comprised of athin, flexible material such as transparent or translucent plastic, isdesigned to cover the capital equipment, such as the instrument driver,robotic arm, and cart (in a cart-based system) or table (in atable-based system). Use of the drape would allow the capital equipmentto be positioned proximate to the patient while still being located inan area not requiring sterilization (i.e., non-sterile field). On theother side of the sterile drape, the medical instrument may interfacewith the patient in an area requiring sterilization (i.e., sterilefield).

D. Medical Instrument.

FIG. 11 illustrates an example medical instrument 1100 with a pairedinstrument driver 1102. Like other instruments designed for use with arobotic system, the medical instrument 1100 (alternately referred to asa “surgical tool”) comprises an elongated shaft 1104 (or elongate body)and an instrument base 1106. The instrument base 1106, also referred toas an “instrument handle” due to its intended design for manualinteraction by the physician, may generally comprise rotatable driveinputs 1108, e.g., receptacles, pulleys or spools, that are designed tobe mated with drive outputs 1110 that extend through a drive interfaceon the instrument driver 1102 at the distal end of a robotic arm 1112.When physically connected, latched, and/or coupled, the mated driveinputs 1108 of the instrument base 1106 may share axes of rotation withthe drive outputs 1110 in the instrument driver 1102 to allow thetransfer of torque from the drive outputs 1110 to the drive inputs 1108.In some embodiments, the drive outputs 1110 may comprise splines thatare designed to mate with receptacles on the drive inputs 1108.

The elongated shaft 1104 is designed to be delivered through either ananatomical opening or lumen, e.g., as in endoscopy, or a minimallyinvasive incision, e.g., as in laparoscopy. The elongated shaft 1104 maybe either flexible (e.g., having properties similar to an endoscope) orrigid (e.g., having properties similar to a laparoscope) or contain acustomized combination of both flexible and rigid portions. Whendesigned for laparoscopy, the distal end of the shaft 1104 may beconnected to an end effector extending from a jointed wrist formed froma clevis with at least one degree of freedom and a surgical tool ormedical instrument, such as, for example, a grasper or scissors, thatmay be actuated based on force from the tendons as the drive inputs 1008rotate in response to torque received from the drive outputs 1110 of theinstrument driver 1102. When designed for endoscopy, the distal end ofthe flexible elongated shaft 1104 may include a steerable orcontrollable bending section that may be articulated and bent based ontorque received from the drive outputs 1110 of the instrument driver1102.

In some embodiments, torque from the instrument driver 1102 istransmitted down the elongated shaft 1104 using tendons along the shaft1104. These individual tendons, such as pull wires, may be individuallyanchored to individual drive inputs 1108 within the instrument handle1106. From the handle 1106, the tendons are directed down one or morepull lumens along the elongated shaft 1104 and anchored at the distalportion of the elongated shaft 1104, or in the wrist at the distalportion of the elongated shaft. During a surgical procedure, such as alaparoscopic, endoscopic, or a hybrid procedure, these tendons may becoupled to a distally mounted end effector, such as a wrist, a grasper,or scissors. Under such an arrangement, torque exerted on the driveinputs 1108 would transfer tension to the tendon, thereby causing theend effector to actuate in some way. In some embodiments, during asurgical procedure, the tendon may cause a joint to rotate about anaxis, thereby causing the end effector to move in one direction oranother. Alternatively, the tendon may be connected to one or more jawsof a grasper at distal end of the elongated shaft 1104, where tensionfrom the tendon cause the grasper to close.

In endoscopy, the tendons may be coupled to a bending or articulatingsection positioned along the elongated shaft 1104 (e.g., at the distalend) via adhesive, control ring, or other mechanical fixation. Whenfixedly attached to the distal end of a bending section, torque exertedon drive inputs 1108 would be transmitted down the tendons, causing thesofter, bending section (sometimes referred to as the articulablesection or region) to bend or articulate. Along the non-bendingsections, it may be advantageous to spiral or helix the individual pulllumens that direct the individual tendons along (or inside) the walls ofthe endoscope shaft to balance the radial forces that result fromtension in the pull wires. The angle of the spiraling and/or spacingthere between may be altered or engineered for specific purposes,wherein tighter spiraling exhibits lesser shaft compression under loadforces, while lower amounts of spiraling results in greater shaftcompression under load forces, but also exhibits limits bending. On theother end of the spectrum, the pull lumens may be directed parallel tothe longitudinal axis of the elongated shaft 1104 to allow forcontrolled articulation in the desired bending or articulable sections.

In endoscopy, the elongated shaft 1104 houses a number of components toassist with the robotic procedure. The shaft may comprise of a workingchannel for deploying surgical tools (or medical instruments),irrigation, and/or aspiration to the operative region at the distal endof the shaft 1104. The shaft 1104 may also accommodate wires and/oroptical fibers to transfer signals to/from an optical assembly at thedistal tip, which may include of an optical camera. The shaft 1104 mayalso accommodate optical fibers to carry light from proximally-locatedlight sources, such as light emitting diodes, to the distal end of theshaft.

At the distal end of the instrument 1100, the distal tip may alsocomprise the opening of a working channel for delivering tools fordiagnostic and/or therapy, irrigation, and aspiration to an operativesite. The distal tip may also include a port for a camera, such as afiberscope or a digital camera, to capture images of an internalanatomical space. Relatedly, the distal tip may also include ports forlight sources for illuminating the anatomical space when using thecamera.

In the example of FIG. 11, the drive shaft axes, and thus the driveinput axes, are orthogonal to the axis of the elongated shaft. Thisarrangement, however, complicates roll capabilities for the elongatedshaft 1104. Rolling the elongated shaft 1104 along its axis whilekeeping the drive inputs 1108 static results in undesirable tangling ofthe tendons as they extend off the drive inputs 1108 and enter pulllumens within the elongated shaft 1104. The resulting entanglement ofsuch tendons may disrupt any control algorithms intended to predictmovement of the flexible elongated shaft during an endoscopic procedure.

FIG. 12 illustrates an alternative design for a circular instrumentdriver 1200 and corresponding instrument 1202 (alternately referred toas a “surgical tool”) where the axes of the drive units are parallel tothe axis of the elongated shaft 1206 of the instrument 1202. As shown,the instrument driver 1200 comprises four drive units with correspondingdrive outputs 1208 aligned in parallel at the end of a robotic arm 1210.The drive units and their respective drive outputs 1208 are housed in arotational assembly 1212 of the instrument driver 1200 that is driven byone of the drive units within the assembly 1212. In response to torqueprovided by the rotational drive unit, the rotational assembly 1212rotates along a circular bearing that connects the rotational assembly1212 to a non-rotational portion 1214 of the instrument driver 1200.Power and control signals may be communicated from the non-rotationalportion 1214 of the instrument driver 1200 to the rotational assembly1212 through electrical contacts maintained through rotation by abrushed slip ring connection (not shown). In other embodiments, therotational assembly 1212 may be responsive to a separate drive unit thatis integrated into the non-rotatable portion 1214, and thus not inparallel with the other drive units. The rotational assembly 1212 allowsthe instrument driver 1200 to rotate the drive units and theirrespective drive outputs 1208 as a single unit around an instrumentdriver axis 1216.

Like earlier disclosed embodiments, the instrument 1202 may include anelongated shaft 1206 and an instrument base 1218 (shown in phantom)including a plurality of drive inputs 1220 (such as receptacles,pulleys, and spools) that are configured to mate with the drive outputs1208 of the instrument driver 1200. Unlike prior disclosed embodiments,the instrument shaft 1206 extends from the center of the instrument base1218 with an axis substantially parallel to the axes of the drive inputs1220, rather than orthogonal as in the design of FIG. 11.

When coupled to the rotational assembly 1212 of the instrument driver1200, the medical instrument 1202, comprising instrument base 1218 andinstrument shaft 1206, rotates in combination with the rotationalassembly 1212 about the instrument driver axis 1216. Since theinstrument shaft 1206 is positioned at the center of the instrument base1218, the instrument shaft 1206 is coaxial with the instrument driveraxis 1216 when attached. Thus, rotation of the rotational assembly 1212causes the instrument shaft 1206 to rotate about its own longitudinalaxis. Moreover, as the instrument base 1218 rotates with the instrumentshaft 1206, any tendons connected to the drive inputs 1220 in theinstrument base 1218 are not tangled during rotation. Accordingly, theparallelism of the axes of the drive outputs 1208, the drive inputs1220, and the instrument shaft 1206 allows for the shaft rotationwithout tangling any control tendons.

FIG. 13 illustrates a medical instrument 1300 having an instrument basedinsertion architecture in accordance with some embodiments. Theinstrument 1300 (alternately referred to as a “surgical tool”) can becoupled to any of the instrument drivers discussed herein above and, asillustrated, can include an elongated shaft 1302, an end effector 1304connected to the shaft 1302, and a handle 1306 coupled to the shaft1302. The elongated shaft 1302 comprises a tubular member having aproximal portion 1308 a and a distal portion 1308 b. The elongated shaft1302 comprises one or more channels or grooves 1310 along its outersurface and configured to receive one or more wires or cables 1312therethrough. One or more cables 1312 thus run along an outer surface ofthe elongated shaft 1302. In other embodiments, the cables 1312 can alsorun through the elongated shaft 1302. Manipulation of the cables 1312(e.g., via an instrument driver) results in actuation of the endeffector 1304.

The instrument handle 1306, which may also be referred to as aninstrument base, may generally comprise an attachment interface 1314having one or more mechanical inputs 1316, e.g., receptacles, pulleys orspools, that are designed to be reciprocally mated with one or moredrive outputs on an attachment surface of an instrument driver.

In some embodiments, the instrument 1300 comprises a series of pulleysor cables that enable the elongated shaft 1302 to translate relative tothe handle 1306. In other words, the instrument 1300 itself comprises aninstrument-based insertion architecture that accommodates insertion ofthe instrument, thereby minimizing the reliance on a robot arm toprovide insertion of the instrument 1300. In other embodiments, arobotic arm can be largely responsible for instrument insertion.

E. Controller.

Any of the robotic systems described herein can include an input deviceor controller for manipulating an instrument attached to a robotic arm.In some embodiments, the controller can be coupled (e.g.,communicatively, electronically, electrically, wirelessly and/ormechanically) with an instrument such that manipulation of thecontroller causes a corresponding manipulation of the instrument e.g.,via master slave control.

FIG. 14 is a perspective view of an embodiment of a controller 1400. Inthe present embodiment, the controller 1400 comprises a hybridcontroller that can have both impedance and admittance control. In otherembodiments, the controller 1400 can utilize just impedance or passivecontrol. In other embodiments, the controller 1400 can utilize justadmittance control. By being a hybrid controller, the controller 1400advantageously can have a lower perceived inertia while in use.

In the illustrated embodiment, the controller 1400 is configured toallow manipulation of two medical instruments, and includes two handles1402. Each of the handles 1402 is connected to a gimbal 1404, and eachgimbal 1404 is connected to a positioning platform 1406.

As shown in FIG. 14, each positioning platform 1406 includes a selectivecompliance assembly robot arm (SCARA) 1408 coupled to a column 1410 by aprismatic joint 1412. The prismatic joints 1412 are configured totranslate along the column 1410 (e.g., along rails 1414) to allow eachof the handles 1402 to be translated in the z-direction, providing afirst degree of freedom. The SCARA arm 1408 is configured to allowmotion of the handle 1402 in an x-y plane, providing two additionaldegrees of freedom.

In some embodiments, one or more load cells are positioned in thecontroller 1400. For example, in some embodiments, a load cell (notshown) is positioned in the body of each of the gimbals 1404. Byproviding a load cell, portions of the controller 1400 are capable ofoperating under admittance control, thereby advantageously reducing theperceived inertia of the controller 1400 while in use. In someembodiments, the positioning platform 1406 is configured for admittancecontrol, while the gimbal 1404 is configured for impedance control. Inother embodiments, the gimbal 1404 is configured for admittance control,while the positioning platform 1406 is configured for impedance control.Accordingly, for some embodiments, the translational or positionaldegrees of freedom of the positioning platform 1406 can rely onadmittance control, while the rotational degrees of freedom of thegimbal 1404 rely on impedance control.

F. Navigation and Control.

Traditional endoscopy may involve the use of fluoroscopy (e.g., as maybe delivered through a C-arm) and other forms of radiation-based imagingmodalities to provide endoluminal guidance to an operator physician. Incontrast, the robotic systems contemplated by this disclosure canprovide for non-radiation-based navigational and localization means toreduce physician exposure to radiation and reduce the amount ofequipment within the operating room. As used herein, the term“localization” may refer to determining and/or monitoring the positionof objects in a reference coordinate system. Technologies such aspre-operative mapping, computer vision, real-time EM tracking, and robotcommand data may be used individually or in combination to achieve aradiation-free operating environment. In other cases, whereradiation-based imaging modalities are still used, the pre-operativemapping, computer vision, real-time EM tracking, and robot command datamay be used individually or in combination to improve upon theinformation obtained solely through radiation-based imaging modalities.

FIG. 15 is a block diagram illustrating a localization system 1500 thatestimates a location of one or more elements of the robotic system, suchas the location of the instrument, in accordance to an exampleembodiment. The localization system 1500 may be a set of one or morecomputer devices configured to execute one or more instructions. Thecomputer devices may be embodied by a processor (or processors) andcomputer-readable memory in one or more components discussed above. Byway of example and not limitation, the computer devices may be in thetower 112 shown in FIG. 1, the cart 102 shown in FIGS. 1-3B, the bedsshown in FIGS. 4-9, etc.

As shown in FIG. 15, the localization system 1500 may include alocalization module 1502 that processes input data 1504 a, 1504 b, 1504c, and 1504 d to generate location data 1506 for the distal tip of amedical instrument. The location data 1506 may be data or logic thatrepresents a location and/or orientation of the distal end of theinstrument relative to a frame of reference. The frame of reference canbe a frame of reference relative to the anatomy of the patient or to aknown object, such as an EM field generator (see discussion below forthe EM field generator).

The various input data 1504 a-d are now described in greater detail.Pre-operative mapping may be accomplished through the use of thecollection of low dose CT scans. Pre-operative CT scans arereconstructed into three-dimensional images, which are visualized, e.g.as “slices” of a cutaway view of the patient's internal anatomy. Whenanalyzed in the aggregate, image-based models for anatomical cavities,spaces and structures of the patient's anatomy, such as a patient lungnetwork, may be generated. Techniques such as center-line geometry maybe determined and approximated from the CT images to develop athree-dimensional volume of the patient's anatomy, referred to as modeldata 1504 a (also referred to as “preoperative model data” whengenerated using only preoperative CT scans). The use of center-linegeometry is discussed in U.S. patent application Ser. No. 14/523,760,the contents of which are herein incorporated in its entirety. Networktopological models may also be derived from the CT-images, and areparticularly appropriate for bronchoscopy.

In some embodiments, the instrument may be equipped with a camera toprovide vision data 1504 b. The localization module 1502 may process thevision data 1504 b to enable one or more vision-based location tracking.For example, the preoperative model data may be used in conjunction withthe vision data 1504 b to enable computer vision-based tracking of themedical instrument (e.g., an endoscope or an instrument advance througha working channel of the endoscope). For example, using the preoperativemodel data 1504 a, the robotic system may generate a library of expectedendoscopic images from the model based on the expected path of travel ofthe endoscope, each image linked to a location within the model.Intra-operatively, this library may be referenced by the robotic systemin order to compare real-time images captured at the camera (e.g., acamera at a distal end of the endoscope) to those in the image libraryto assist localization.

Other computer vision-based tracking techniques use feature tracking todetermine motion of the camera, and thus the endoscope. Some features ofthe localization module 1502 may identify circular geometries in thepreoperative model data 1504 a that correspond to anatomical lumens andtrack the change of those geometries to determine which anatomical lumenwas selected, as well as the relative rotational and/or translationalmotion of the camera. Use of a topological map may further enhancevision-based algorithms or techniques.

Optical flow, another computer vision-based technique, may analyze thedisplacement and translation of image pixels in a video sequence in thevision data 1504 b to infer camera movement. Examples of optical flowtechniques may include motion detection, object segmentationcalculations, luminance, motion compensated encoding, stereo disparitymeasurement, etc. Through the comparison of multiple frames overmultiple iterations, movement and location of the camera (and thus theendoscope) may be determined.

The localization module 1502 may use real-time EM tracking to generate areal-time location of the endoscope in a global coordinate system thatmay be registered to the patient's anatomy, represented by thepreoperative model. In EM tracking, an EM sensor (or tracker) comprisingof one or more sensor coils embedded in one or more locations andorientations in a medical instrument (e.g., an endoscopic tool) measuresthe variation in the EM field created by one or more static EM fieldgenerators positioned at a known location. The location informationdetected by the EM sensors is stored as EM data 1504 c. The EM fieldgenerator (or transmitter), may be placed close to the patient to createa low intensity magnetic field that the embedded sensor may detect. Themagnetic field induces small currents in the sensor coils of the EMsensor, which may be analyzed to determine the distance and anglebetween the EM sensor and the EM field generator. These distances andorientations may be intra-operatively “registered” to the patientanatomy (e.g., the preoperative model) in order to determine thegeometric transformation that aligns a single location in the coordinatesystem with a position in the pre-operative model of the patient'sanatomy. Once registered, an embedded EM tracker in one or morepositions of the medical instrument (e.g., the distal tip of anendoscope) may provide real-time indications of the progression of themedical instrument through the patient's anatomy.

Robotic command and kinematics data 1504 d may also be used by thelocalization module 1502 to provide localization data 1506 for therobotic system. Device pitch and yaw resulting from articulationcommands may be determined during pre-operative calibration.Intra-operatively, these calibration measurements may be used incombination with known insertion depth information to estimate theposition of the instrument. Alternatively, these calculations may beanalyzed in combination with EM, vision, and/or topological modeling toestimate the position of the medical instrument within the network.

As FIG. 15 shows, a number of other input data can be used by thelocalization module 1502. For example, although not shown in FIG. 15, aninstrument utilizing shape-sensing fiber can provide shape data that thelocalization module 1502 can use to determine the location and shape ofthe instrument.

The localization module 1502 may use the input data 1504 a-d incombination(s). In some cases, such a combination may use aprobabilistic approach where the localization module 1502 assigns aconfidence weight to the location determined from each of the input data1504 a-d. Thus, where the EM data 1504 c may not be reliable (as may bethe case where there is EM interference) the confidence of the locationdetermined by the EM data 1504 c can be decrease and the localizationmodule 1502 may rely more heavily on the vision data 1504 b and/or therobotic command and kinematics data 1504 d.

As discussed above, the robotic systems discussed herein may be designedto incorporate a combination of one or more of the technologies above.The robotic system's computer-based control system, based in the tower,bed and/or cart, may store computer program instructions, for example,within a non-transitory computer-readable storage medium such as apersistent magnetic storage drive, solid state drive, or the like, that,upon execution, cause the system to receive and analyze sensor data anduser commands, generate control signals throughout the system, anddisplay the navigational and localization data, such as the position ofthe instrument within the global coordinate system, anatomical map, etc.

2. Introduction.

Embodiments of the disclosure relate to robotic surgical tools thatincorporate one or more rotary cables to cause actuation of the surgicaltool. One robotic surgical tool includes a drive housing having a firstend, a second end, and a lead screw extending between the first andsecond ends. A carriage is movably mounted to the lead screw at acarriage nut secured to the carriage, and an activating mechanismincluding a drive gear is rotatably mounted to the carriage androtatable to actuate the activating mechanism. A torsion cable extendsbetween the drive gear and a drive input arranged at the first end.Rotating the drive input causes the torsion cable to rotate and therebytransmits a torsional load along the torsion cable to the drive gear toactuate the activating mechanism.

3. Description.

FIG. 16 is an isometric side view of an example surgical tool 1600 thatmay incorporate some or all of the principles of the present disclosure.The surgical tool 1600 may be similar in some respects to any of themedical instruments described above with reference to FIGS. 11-13 and,therefore, may be used in conjunction with a robotic surgical system,such as the robotically-enabled systems 100, 400, and 900 of FIGS. 1-13.As illustrated, the surgical tool 1600 includes an elongated shaft 1602,an end effector 1604 arranged at the distal end of the shaft 1602, andan articulable wrist 1606 (alternately referred to as a “wrist joint”)that interposes and couples the end effector 1604 to the distal end ofthe shaft 1602.

The terms “proximal” and “distal” are defined herein relative to arobotic surgical system having an interface configured to mechanicallyand electrically couple the surgical tool 1600 to a robotic manipulator.The term “proximal” refers to the position of an element closer to therobotic manipulator and the term “distal” refers to the position of anelement closer to the end effector 1604 and thus closer to the patientduring operation. Moreover, the use of directional terms such as above,below, upper, lower, upward, downward, left, right, and the like areused in relation to the illustrative embodiments as they are depicted inthe figures, the upward or upper direction being toward the top of thecorresponding figure and the downward or lower direction being towardthe bottom of the corresponding figure.

The surgical tool 1600 can have any of a variety of configurationscapable of performing one or more surgical functions. In the illustratedembodiment, the end effector 1604 comprises a surgical stapler,alternately referred to as an “endocutter,” configured to cut and staple(fasten) tissue. As illustrated, the end effector 1604 includes opposingjaws 1610, 1612 configured to move (articulate) between open and closedpositions. Alternatively, the end effector 1604 may comprise other typesof instruments requiring opposing jaws such as, but not limited to,other surgical staplers (e.g., circular and linear staplers), tissuegraspers, surgical scissors, advanced energy vessel sealers, clipappliers, needle drivers, a babcock including a pair of opposed graspingjaws, bipolar jaws (e.g., bipolar Maryland grasper, forceps, afenestrated grasper, etc.), etc. In other embodiments, the end effector1604 may instead comprise any end effector or instrument capable ofbeing operated in conjunction with the presently disclosed roboticsurgical systems and methods. Such end effectors or instruments include,but are not limited to, a suction irrigator, an endoscope (e.g., acamera), or any combination thereof.

One or both of the jaws 1610, 1612 may be configured to pivot to actuatethe end effector 1604 between open and closed positions. In theillustrated example, the second jaw 1612 is rotatable (pivotable)relative to the first jaw 1610 to move between an open, unclampedposition and a closed, clamped position. In other embodiments, however,the first jaw 1610 may move (rotate) relative to the second jaw 1612,without departing from the scope of the disclosure. In yet otherembodiments, both jaws 1610, 1612 may move to actuate the end effector1604 between open and closed positions.

In the illustrated example, the first jaw 1610 is referred to as a“cartridge” or “channel” jaw, and the second jaw 1612 is referred to asan “anvil” jaw. The first jaw 1610 may include a frame that houses orsupports a staple cartridge, and the second jaw 1612 is pivotallysupported relative to the first jaw 1610 and defines a surface thatoperates as an anvil to deform staples ejected from the staple cartridgeduring operation.

The wrist 1606 enables the end effector 1604 to articulate (pivot)relative to the shaft 1602 and thereby position the end effector 1604 atvarious desired orientations and locations relative to a surgical site.In the illustrated embodiment, the wrist 1606 is designed to allow theend effector 1604 to pivot (swivel) left and right relative to alongitudinal axis A₁ of the shaft 1602. In other embodiments, however,the wrist 1606 may be designed to provide multiple degrees of freedom,including one or more translational variables (i.e., surge, heave, andsway) and/or one or more rotational variables (i.e., Euler angles orroll, pitch, and yaw). The translational and rotational variablesdescribe the position and orientation of a component of a surgicalsystem (e.g., the end effector 1604) with respect to a given referenceCartesian frame. “Surge” refers to forward and backward translationalmovement, “heave” refers to translational movement up and down, and“sway” refers to translational movement left and right. With regard tothe rotational terms, “roll” refers to tilting side to side, “pitch”refers to tilting forward and backward, and “yaw” refers to turning leftand right.

In the illustrated embodiment, the pivoting motion at the wrist 1606 islimited to movement in a single plane, e.g., only yaw movement relativeto the longitudinal axis A₁. The end effector 1604 is depicted in FIG.16 in the unarticulated position where the longitudinal axis of the endeffector 1604 is substantially aligned with the longitudinal axis A₁ ofthe shaft 1602, such that the end effector 1604 is at a substantiallyzero angle relative to the shaft 1602. In the articulated position, thelongitudinal axis of the end effector 1604 would be angularly offsetfrom the longitudinal axis A₁ such that the end effector 1604 would beoriented at a non-zero angle relative to the shaft 1602.

Still referring to FIG. 16, the surgical tool 1600 may include a drivehousing 1614 that houses an actuation system designed to facilitatearticulation of the wrist 1606 and actuation (operation) of the endeffector 1604 (e.g., clamping, firing, rotation, articulation, energydelivery, etc.). The drive housing 1614, alternately referred to as a“stage,” provides various coupling features that releasably couple thesurgical tool 1600 to an instrument driver of a robotic surgical system,as described in more detail below.

The drive housing 1614 includes a plurality of drive members (obscuredin FIG. 16) that extend to the wrist 1606 and the end effector 1604.Selective actuation of one or more of the drive members causes the endeffector 1604 to articulate (pivot) relative to the shaft 1602 at thewrist 1606. Selective actuation of one or more other drive memberscauses the end effector 1604 to actuate (operate). Actuating the endeffector 1604 may include closing and/or opening the jaws, 1610, 1612,and thereby enabling the end effector 1604 to grasp (clamp) onto tissue.Once tissue is grasped or clamped between the opposing jaws 1610, 1612,actuating the end effector 1604 may further include “firing” the endeffector 1604, which may refer to causing a cutting element or knife(not visible) to advance distally within a slot 1616 defined in thefirst jaw 1610. As it moves distally, the cutting element transects anytissue grasped between the opposing jaws 1610, 1612. Moreover, as thecutting element advances distally, a plurality of staples containedwithin the staple cartridge (e.g., housed within the first jaw 1610) areurged (cammed) into deforming contact with corresponding anvil surfaces(e.g., pockets) provided on the second jaw 1612. The deployed staplesmay form multiple rows of staples that seal opposing sides of thetransected tissue.

As illustrated, the drive housing 1614 has a first or “distal” end 1618a and a second or “proximal” end 1618 b opposite the first end 1618 a.The first end 1618 a is alternately referred to as a “handle.” In someembodiments, one or more struts 1620 (two shown) extend longitudinallybetween the first and second ends 1618 a,b to help fix the distancebetween the first and second ends 1618 a,b, provide advantageousstructural stability to the drive housing 1614, and secure the first end1618 a to the second end 1618 b. In other embodiments, however, thestruts 1620 may be omitted, without departing from the scope of thedisclosure.

The drive housing 1614 may also include a lead screw 1622 and one ormore splines 1624, which also extend longitudinally between the firstand second ends 1618 a,b. In the illustrated embodiment, the drivehousing 1614 includes a first spline 1624 a, a second spline 1624 b, anda third spline 1624 c. While three splines 1624 a-c are depicted in thedrive housing 1614, more or less than three may be included, withoutdeparting from the scope of the disclosure. Unlike the struts 1620, thelead screw 1622 and the splines 1624 a-c are rotatably mounted to thefirst and second ends 1618 a,b. As described in more detail below,selective rotation of the lead screw 1622 and the splines 1624 a-ccauses various functions of the drive housing 1614 to transpire, such astranslating the end effector 1604 along the longitudinal axis A₁ (e.g.,z-axis translation) causing the end effector 1604 to articulate (pivot)at the wrist 1606, causing the jaws 1610, 1612 to open and close, andcausing the end effector 1604 to fire (operate).

The drive housing 1614 further includes a carriage 1626 movably mountedalong the lead screw 1622 and the splines 1624 a-c and houses variousactivating mechanisms configured to cause operation of specificfunctions of the end effector 1604. The carriage 1626 may comprise twoor more layers, shown in FIG. 16 as a first layer 1628 a, a second layer1628 b, a third layer 1628 c, a fourth layer 1628 d, and a fifth layer1628 e. The lead screw 1622 and the splines 1624 a-c each extend throughportions of one or more of the layers 1628 a-e to allow the carriage1626 to translate along the longitudinal axis A₁ with respect to thelead screw 1622 and the splines 1624 a-c. In some embodiments, thelayers 1628 a-e may be secured to each other in series using one or moremechanical fasteners 1630 (two visible) extending between the firstlayer 1628 a and the fifth layer 1628 e and through coaxially alignedholes defined in some or all of the layers 1628 a-e. While five layers1628 a-e are depicted, more or less than five may be included in thecarriage 1626, without departing from the scope of the disclosure.

The shaft 1602 is coupled to and extends distally from the carriage 1626through the first end 1618 a of the drive housing 1614. In theillustrated embodiment, for example, the shaft 1602 penetrates the firstend 1618 a at a central aperture 1632 defined through the first end 1618a. The carriage 1626 is movable between the first and second ends 1618a,b along the longitudinal axis A₁ (e.g., z-axis translation) and isthereby able to advance or retract the end effector 1604 relative to thedrive housing 1614, as indicated by the arrows B. More specifically, insome embodiments, the carriage 1626 includes a carriage nut 1634 mountedto the lead screw 1622 and secured between the third and fourth layers1628 c,d. The outer surface of the lead screw 1622 defines outer helicalthreading and the carriage nut 1634 defines corresponding internalhelical threading (not shown) matable with the outer helical threadingof the lead screw 1622. As a result, rotation of the lead screw 1622causes the carriage nut 1634 to advance or retract the carriage 1626along the longitudinal axis A₁ and correspondingly advance or retractthe end effector 1604 relative to the drive housing 1614.

As indicated above, the lead screw 1622 and the splines 1624 a-c arerotatably mounted to the first and second ends 1618 a,b. Morespecifically, the first end 1618 a of the drive housing 1614 may includeone or more rotatable drive inputs actuatable to independently drive(rotate) the lead screw 1622 and the splines 1624 a-c. In theillustrated embodiment, the drive housing 1614 includes a first driveinput 1636 a, a second drive input 1636 b, a third drive input 1636 c(occluded by the shaft 1602, see FIG. 17B), and a fourth drive input1636 d. As described below, each drive input 1636 a-d may be matablewith a corresponding drive output of an instrument driver such thatmovement (rotation) of a given drive output correspondingly moves(rotates) the associated drive input 1636 a-d and thereby rotates themated lead screw 1622 or spline 1624 a-c. While only four drive inputs1636 a-d are depicted, more or less than four may be included in thedrive housing 1614, depending on the application.

The first drive input 1636 a may be operatively coupled to the leadscrew 1622 such that rotation of the first drive input 1636 acorrespondingly rotates the lead screw 1622, which causes the carriagenut 1634 and the carriage 1626 to advance or retract along thelongitudinal axis A₁, depending on the rotational direction of the leadscrew 1622. As used herein the phrase “operatively coupled” refers to acoupled engagement, either directly or indirectly, where movement of onecomponent causes corresponding movement of another component. Withrespect to the first drive input 1636 a being operatively coupled to thelead screw 1622, such operative coupling may be facilitated throughintermeshed gears (not shown) arranged within the second end 1618 a, butcould alternatively be facilitated through other mechanical means, suchas cables, pulleys, drive rods, direct couplings, etc., withoutdeparting from the scope of the disclosure.

The second drive input 1636 b may be operatively coupled to the firstspline 1624 a such that rotation of the second drive input 1636 bcorrespondingly rotates the first spline 1624 a. In some embodiments,the first spline 1624 a may be operatively coupled to a first activatingmechanism 1638 a of the carriage 1626, and the first activatingmechanism 1638 a may be operable to open and close the jaws 1610, 1612.Accordingly, rotating the second drive input 1636 b will correspondinglyactuate the first activating mechanism 1638 a and thereby open or closethe jaws 1610, 1612, depending on the rotational direction of the firstspline 1624 a.

The third drive input 1636 c may be operatively coupled to the secondspline 1624 b such that rotation of the third drive input 1636 ccorrespondingly rotates the second spline 1624 b. In some embodiments,the second spline 1624 b may be operatively coupled to a secondactivating mechanism 1638 b of the carriage 1626, and the secondactivating mechanism 1638 b may be operable to articulate the endeffector 1604 at the wrist 1606. Accordingly, rotating the third driveinput 1636 c will correspondingly actuate the second activatingmechanism 1638 b and thereby cause the wrist 1606 to articulate in atleast one degree of freedom, depending on the rotational direction ofthe second spline 1624 b.

The fourth drive input 1636 d may be operatively coupled to the thirdspline 1624 c such that rotation of the fourth drive input 1636 dcorrespondingly rotates the third spline 1624 c. In some embodiments,the third spline 1624 c may be operatively coupled to a third activatingmechanism 1638 c of the carriage 1626, and the third activatingmechanism 1638 c may be operable to fire the cutting element (knife) atthe end effector 1604. Accordingly, rotating the fourth drive input 1636d will correspondingly actuate the third activating mechanism 1638 c andthereby cause the knife to advance or retract, depending on therotational direction of the third spline 1624 c.

In the illustrated embodiment, and as described in more detail below,the activating mechanisms 1638 a-c comprise intermeshed gearingassemblies including one or more drive gears driven by rotation of thecorresponding spline 1624 a-c and configured to drive one or morecorresponding driven gears that cause operation of specific functions ofthe end effector 1604. It is further contemplated herein, however, thatthe activating mechanisms 1638 a-c may be operated through other typesof mechanical cooperation such as, but not limited to, belts or cables.

In some embodiments, the drive housing 1614 may include a shroud 1640sized to receive and otherwise surround the carriage 1626, the leadscrew 1622, and the splines 1624 a-c. In the illustrated embodiment, theshroud 1640 comprises a tubular or cylindrical structure having a firstend 1642 a matable with the first end 1618 a of the drive housing 1614,and a second end 1642 b matable with the second end 1618 b of the drivehousing 1614. The carriage 1626, the lead screw 1622, and the splines1624 a-c can all be accommodated within the interior of the shroud 1640,and the carriage 1626 may engage and traverse (ride on) one or morerails 1644 (shown in phantom) fixed to the shroud 1640. The rails 1644extend longitudinally and parallel to the lead screw 1622 and are sizedto be received within corresponding notches 1646 defined on the outerperiphery of the carriage 1626 and, more particularly, on the outerperiphery of one or more of the carriage layers 1628 a-e. As thecarriage 1626 translates along the longitudinal axis A₁, the rails 1644help maintain the angular position of the carriage 1626 and assume anytorsional loading that might otherwise adversely affect movement oroperation of the carriage 1626.

FIG. 17A is an isometric view of the surgical tool 1600 of FIG. 16releasably coupled to an example instrument driver 1702, according toone or more embodiments. The instrument driver 1702 may be similar insome respects to the instrument drivers 1102, 1200 of FIGS. 11 and 12,respectively, and therefore may be best understood with referencethereto. Similar to the instrument drivers 1102, 1200, for example, theinstrument driver 1702 may be mounted to or otherwise positioned at theend of a robotic arm (not shown) and is designed to provide the motiveforces required to operate the surgical tool 1600. Unlike the instrumentdrivers 1102, 1200, however, the shaft 1602 of the surgical tool 1600extends through and penetrates the instrument driver 1702.

The instrument driver 1702 has a body 1704 having a first or “proximal”end 1706 a and a second or “distal” end 1706 b opposite the first end1706 a. In the illustrated embodiment, the first end 1706 a of theinstrument driver 1702 is matable with and releasably coupled to thefirst end 1618 a of the drive housing 1614, and the shaft 1602 of thesurgical tool 1600 extends through the body 1704 and distally from thesecond end 1706 b.

FIG. 17B depicts separated isometric end views of the instrument driver1702 and the surgical tool 1600 of FIG. 17A. With the jaws 1610, 1612closed, the shaft 1602 and the end effector 1604 can penetrate theinstrument driver 1702 by extending through a central aperture 1708defined longitudinally through the body 1704 between the first andsecond ends 1706 a,b. To align the surgical tool 1600 with theinstrument driver 1702 in a proper angular orientation, one or morealignment guides 1710 may be provided or otherwise defined within thecentral aperture 1708 and configured to engage one or more correspondingalignment features 1712 provided on the surgical tool 1600. In theillustrated embodiment, the alignment feature 1712 comprises aprotrusion or projection defined on or otherwise provided by analignment nozzle 1714 extending distally from the first end 1618 a ofthe drive housing 1614. In one or more embodiments, the alignment guide1710 may comprise a curved or arcuate shoulder or lip configured toreceive and guide the alignment feature 1712 as the alignment nozzle1714 enters the central aperture 1708. As a result, the surgical tool1600 is oriented to a proper angular alignment with the instrumentdriver 1702 as the alignment nozzle 1714 is advanced distally throughthe central aperture 1708. In other embodiments, the alignment nozzle1714 may be omitted and the alignment feature 1712 may alternatively beprovided on the shaft 1602, without departing from the scope of thedisclosure.

As illustrated, a drive interface 1716 is provided at the first end 1706a of the instrument driver 1702, and a driven interface 1718 is providedat the first end 1618 a of the drive housing 1614. The drive and driveninterfaces 1716, 1718 may be configured to mechanically, magnetically,and/or electrically couple the drive housing 1614 to the instrumentdriver 1702. To accomplish this, the drive and driven interfaces 1716,1718 may provide one or more matable locating features configured tosecure the drive housing 1614 to the instrument driver 1702. In theillustrated embodiment, for example, the drive interface 1716 providesone or more interlocking features 1720 (three shown) configured tolocate and mate with one or more complementary-shaped pockets 1722 (twoshown, one occluded) provided on the driven interface 1718. In someembodiments, the features 1720 may be configured to align and mate withthe pockets 1722 via an interference or snap fit engagement, forexample.

The instrument driver 1702 also includes one or more drive outputs thatextend through the drive interface 1716 to mate with the drive inputs1636 a-d provided at the first end 1618 a of the drive housing 1614.More specifically, the instrument driver 1702 includes a first driveoutput 1724 a matable with the first drive input 1636 a, a second driveoutput 1724 b matable with the second drive input 1636 b, a third driveoutput 1724 b matable with the third drive input 1636 c, and a fourthdrive output 1724 d matable with the fourth drive input 1636 d. In someembodiments, as illustrated, the drive outputs 1724 a-d may definesplines or features designed to mate with corresponding splinedreceptacles of the drive inputs 1636 a-d. Once properly mated, the driveinputs 1636 a-d will share axes of rotation with the corresponding driveoutputs 1724 a-d to allow the transfer of rotational torque from thedrive outputs 1724 a-d to the corresponding drive inputs 1636 a-d. Insome embodiments, each drive output 1724 a-d may be spring loaded andotherwise biased to spring outwards away from the drive interface 1716.Each drive output 1724 a-d may be capable of partially or fullyretracting into the drive interface 1716.

In some embodiments, the instrument driver 1702 may include additionaldrive outputs, depicted in FIG. 17B as a fifth drive output 1724 e and asixth drive output 1724 f. The fifth and sixth drive outputs 1724 e,fmay be configured to mate with additional drive inputs (not shown) ofthe drive housing 1614 to help undertake one or more additionalfunctions of the surgical tool 1600. In the illustrated embodiment,however, the drive housing 1614 does not include additional drive inputsmatable with the fifth and sixth drive outputs 1724 e,f. Instead, thedriven interface 1718 defines corresponding recesses 1726 configured toreceive the fifth and sixth drive outputs 1724 e,f. In otherapplications, however, fifth and/or sixth drive inputs (not shown) couldbe included in the drive housing 1614 to mate with the fifth and sixthdrive outputs 1724 e,f, or the surgical tool 1600 might be replaced withanother surgical tool having fifth and/or sixth drive inputs, whichwould be driven by the fifth and/or sixth drive outputs 1724 e,f.

While not shown, in some embodiments, an instrument sterile adapter(ISA) may be placed at the interface between the instrument driver 1702and the surgical tool 1600. In such applications, the interlockingfeatures 1720 may operate as alignment features and possible latches forthe ISA to be placed, stabilized, and secured. Stability of the ISA maybe accomplished by a nose cone feature provided by the ISA and extendinginto the central aperture 1708 of the instrument driver 1702. Latchingcan occur either with the interlocking features 1720 or at otherlocations at the interface. In some cases, the ISA will provide themeans to help align and facilitate the latching of the surgical tool1600 to the ISA and simultaneously to the instrument driver 1702.

Articulation Mechanisms

FIG. 18A is an enlarged isometric view of an embodiment of the carriage1626 and the second activating mechanism 1638 b. As mentioned above, thesecond spline 1624 b can be operatively coupled to the second activatingmechanism 1638 b such that rotating the second spline 1624 b (viarotation of the third drive input 1636 c of FIGS. 16 and 17B) willcorrespondingly actuate the second activating mechanism 1638 b andthereby cause the wrist 1606 (FIG. 16) to articulate. As illustrated,the second spline 1624 b extends longitudinally through coaxiallyaligned apertures 1802 defined in the second and third layers 1628 b,cof the carriage 1626. In some embodiments, for example, each aperture1802 may be defined in a corresponding lobe 1804 provided by each of thesecond and third layers 1628 b,c.

A drive gear 1806 may be included with the second spline 1624 b andlocated between the second and third layers 1628 b,c and, moreparticularly, between the lobes 1804 of each layer 1628 b,c. The secondspline 1624 b may exhibit a cross-sectional shape matable with the drivegear 1806 such that rotation of the second spline 1624 b correspondinglydrives the drive gear 1806 in rotation. In some embodiments, the drivegear 1806 may comprise a separate component part slidably disposed aboutthe second spline 1624 b. In such embodiments, as the carriage 1626moves along the longitudinal axis A₁ (FIG. 16), the drive gear 1806 willmove along the length of the second spline 1624 b as captured betweenthe second and third layers 1628 b,c. In other embodiments, however, thesecond spline 1624 b may be shaped and otherwise configured to operateas the drive gear 1806 to advantageously reduce the number of componentparts.

The drive gear 1806 may be positioned on the carriage 1626 tosimultaneously intermesh with a first or “distal” transfer gear 1808 aand a second or “proximal” transfer gear 1808 b. Accordingly, as thespline 1624 b is rotated, the drive gear 1806 drives the first andsecond transfer gears 1808 a,b simultaneously.

FIG. 18B is an enlarged side view of the carriage 1626 and the secondactivating mechanism 1638 b. The second and third layers 1626 b,c (FIG.18A) of the carriage 1626 are omitted in FIG. 18B to enable a more fullview of the second activating mechanism 1638 b. The first and secondtransfer gears 1808 a,b may comprise annular structures that extendabout the shaft 1602 and, more particularly, about an inner groundingmember or shaft 1810 that forms part of the shaft 1602. The innergrounding shaft 1810 extends concentrically within an outer portion ofthe shaft 1602, referred to herein as a closure tube 1812.

The second activating mechanism 1638 b may further include a first or“distal” carrier 1814 a (partially visible) and a second or “proximal”carrier 1814 b (shown in dashed lines). The first carrier 1814 aradially interposes the inner grounding shaft 1810 and at least aportion of the first transfer gear 1808 a, and the second carrier 1814 bradially interposes the inner grounding shaft 1810 and at least aportion of the second transfer gear 1808 b. The first and secondtransfer gears 1808 a,b are internally threaded in opposite directions(i.e., one left-handed and the other right-handed), and the firsttransfer gear 1808 a may threadably engage external threads defined bythe first carrier 1814 a while the second transfer gear 1808 b maythreadably engage external threads defined by the second carrier 1814 b.

FIG. 18C is an isometric, cross-sectional side view of the secondactivating mechanism 1638 b, according to one or more embodiments. Asillustrated, the first and second carriers 1814 a,b radially interposethe inner grounding shaft 1810 and the first and second transfer gears1808 a,b, respectively, as mentioned above. Moreover, the first carrier1814 a may be operatively coupled to or otherwise mate with a firstdrive member 1816 a, which extends distally to the wrist 1606 (FIG. 16).As illustrated, the first drive member 1816 a is arranged within acorresponding slot 1818 defined in the inner grounding shaft 1810, whichguides the first drive member 1816 a as it extends to the wrist 1606.Similarly, the second carrier 1814 b may be operatively coupled to orotherwise mate with a second drive member 1816 b, which extends distallyto the wrist 1606. The second drive member 1816 b is also arrangedwithin a corresponding slot 1820 defined in the inner grounding shaft1810, which guides the second drive member 1816 b as it extends to thewrist 1606.

The first transfer gear 1808 a defines internal threading 1822 a matablewith external threading 1824 a defined on the outer surface of the firstcarrier 1814 a, and the second transfer gear 1808 b similarly definesinternal threading 1822 b matable with external threading 1824 b definedon the outer surface of the second carrier 1814 b. The internalthreadings 1822 a,b are oppositely threaded; i.e., one comprisesleft-handed threads and the other comprises right-handed threads.Consequently, as the drive gear 1806 rotates, it simultaneously drivesboth transfer gears 1808 a,b in rotation, which, in turn, simultaneouslydrives the corresponding carriers 1814 a,b in equal but opposite axialdirections because of the oppositely threaded engagement of the internalthreadings 1822 a,b. Depending on the rotation direction of the drivegear 1806, the carriers 1814 a,b may be drawn axially toward each otheror moved axially away from each other.

Opposite axial movement of the first and second carriers 1814 a,brelative to the inner grounding shaft 1810 and along the longitudinalaxis A₁ (FIG. 16) correspondingly moves the drive members 1816 a,b inthe same opposite axial directions and, thereby, articulates the endeffector 1604 (FIGS. 16 and 17B). In at least one embodiment, the firstand second carriers 1814 a,b antagonistically operate such that one ofthe carriers 1814 a,b pulls one of the drive members 1816 a,b proximallywhile the other carrier 1814 a,b simultaneously pushes the other drivemember 1816 a,b distally. A gap 1826 provided between the carriers 1814a,b along the inner grounding shaft 1810 allows the carriers 1814 a,b tomove toward and away from one another, and thereby provides clearance tofacilitate clockwise and counter-clockwise articulation. As the carriers1814 a,b are drawn axially toward each other, the end effector 1604 willarticulate in a first direction, and as the carriers 1814 a,b are movedaxially away from each other, the end effector 1604 will articulate in asecond direction opposite the first direction.

Referring to FIG. 19, with continued reference to FIG. 18C, depicted isan enlarged view of the end effector 1604 and an exposed view of thewrist 1606, according to one or more embodiments. In FIG. 19, the innergrounding shaft 1810 (FIGS. 18B-18C) has been removed to enable viewingof how the drive members 1816 a,b interconnect with or are otherwiseoperatively connected to the end effector 1604. In the illustratedembodiment, the end effector 1604 is mounted to an end effector mount1902 that defines or otherwise provides two articulation pins 1904, andthe distal end of each drive member 1816 a,b is rotatably mounted to acorresponding one of the articulation pins 1904. The drive members 1816a,b are also interconnected at the distal ends via a distal link 1906,which together comprise a linkage configured to help articulate endeffector mount 1902, and therefore the end effector 1604, in a planeparallel to the longitudinal axis A₁.

In this configuration, the drive members 1816 a,b translateantagonistically and parallel along the longitudinal axis A₁, such thatas the first drive member 1816 a moves distally the second drive member1816 b moves proximally, and vice versa. Moreover, distal movement ofthe first drive member 1816 a and simultaneous proximal movement of thesecond drive member 1816 b cooperatively act on the end effector mount1902 to cause the end effector 1604 to rotate counter-clockwise, asindicated by the arrow C₁. In contrast, proximal movement of the firstdrive member 1816 a and simultaneous distal movement of the second drivemember 1816 b cooperatively act on the end effector mount 1902 to causethe end effector 1604 to rotate clockwise, as indicated by the arrow C₂.

FIG. 20 is an enlarged cross-sectional side view of another embodimentof the second activating mechanism 1638 b. The embodiment shown in FIG.20 is similar in some respects to the embodiment of the secondactivating mechanism 1638 b of FIGS. 18A-18C and, therefore, may be bestunderstood with reference thereto. Similar to the embodiment of FIGS.18A-18C, for example, the second activating mechanism 1638 b of FIG. 20includes the first and second carriers 1814 a,b radially interposing theinner grounding shaft 1810 and the first and second transfer gears 1808a,b, respectively. Moreover, the first carrier 1814 a is operativelycoupled to or otherwise mates with the first drive member 1816 a, andthe second carrier 1814 b operatively couples to or otherwise mates withthe second drive member 1816 b, and the drive members 1816 a,b extenddistally to the wrist 1606 (FIGS. 16 and 19). The internal threading1822 a of the first transfer gear 1808 a mates with the externalthreading 1824 a of the first carrier 1814 a, and the internal threading1822 b of the second transfer gear 1808 b similarly mates with theexternal threading 1824 b of the second carrier 1814 b, and the internalthreadings 1822 a,b are again oppositely threaded.

Unlike the embodiment of the second activating mechanism 1638 b of FIGS.18A-18C, however, the embodiment of FIG. 20 includes two splines and twocorresponding drive gears. More specifically, a first drive gear 2002 amay be included with the second spline 1624 b such that rotation of thesecond spline 1624 b correspondingly rotates the first drive gear 2002a, and a second drive gear 2002 b may be included with a fourth spline1624 d such that rotation of the fourth spline 1624 d correspondinglyrotates the second drive gear 2002 b. As mentioned above, the thirddrive output 1724 b (FIG. 17B) may drive the third drive input 1636 c(FIGS. 16 and 17B) to rotate the second spline 1624 b. In one or moreembodiments, the fourth spline 1624 d may be operatively coupled to afifth drive input (not shown) at the first end 1618 a of the drivehousing 1614 (FIGS. 16 and 17B) and driven by one of the fifth or sixthdrive outputs 1724 e,f (FIG. 17B). In such embodiments, actuation of thefifth or sixth drive output 1724 e,f will correspondingly cause thefourth spline 1624 d to rotate and thereby rotate the second drive gear2002 b.

Both drive gears 2002 a,b may be located between the second and thirdlayers 1628 b,c. The first drive gear 2002 a may be positioned tointermesh with the first transfer gear 1808 a, and the second drive gear2002 b may be positioned to intermesh with the second transfer gear 1808b. As the first drive gear 2002 a rotates, the first transfer gear 1808a is correspondingly rotated and drives the first carrier 1814 a axiallyalong the longitudinal axis A₁ because of the threaded engagement of theintermeshed internal and external threadings 1822 a, 1824 a. Similarly,as the second drive gear 2002 b rotates, the second transfer gear 1808 bcorrespondingly rotates and drives the second carrier 1814 b axiallyalong the longitudinal axis A₁ because of the threaded engagement of theintermeshed internal and external threadings 1822 b, 1824 b. Dependingon the rotation direction of the drive gears 2002 a,b, the carriers 1814a,b may be moved axially toward or away from each other.

Axial movement of the first and second carriers 1814 a,b along thelongitudinal axis A₁ cooperatively actuates the drive members 1816 a,b,and thereby articulates the end effector 1604 (FIGS. 16 and 19). In atleast one embodiment, the first and second carriers 1814 a,bprotagonistically operate such that one of the carriers 1814 a,b pullsone of the drive members 1816 a,b proximally while the other carrier1814 a,b pushes the other drive member 1816 a,b distally. In someembodiments, however, the first and second carriers 1814 a,b may beoperated independently without the other being operated (affected), thusoperating antagonistically where one reduces the force effect of theother. In antagonistic operation, one of the carriers 1814 a,b pulls (orpushes) the drive member 1816 a,b associated therewith proximally (ordistally) with a first force while the other one of the carriers 1814a,b pulls (or pushes) the drive member 1816 a,b associated therewithproximally (or distally) with a second force, where the first force islarger than the second force such that the first force can overcome thesecond force, as well as the internal losses of the device (i.e.,friction) and loads imparted on the end effector 1604 via the externalenvironment. As will be appreciated, this ensures that the carrier 1814a,b providing the first force moves proximally (or distally) while thecarrier 1815 a,b providing the second force moves distally (orproximally).

Software stored on a computer system may be configured to control thedrive outputs 1724 b and 1724 e or 1724 f (FIG. 17B) that drive rotationof the second and fourth splines 1624 b,d, respectively, to therebysynchronize actuation (movement) of the carriers 1814 a,b and thecorresponding drive members 1816 a,b. In some embodiments, the softwaremay further be configured to reduce lag or slop (slack) in movement ofthe carriers 1814 a,b, which correspondingly reduces lag or slop (slack)in articulation of the end effector 1604. In the embodiment of FIG. 20,for example, one drive output 1724 b or 1724 e,f may turncounter-clockwise while the other drive output 1724 b or 1724 e,fcompensates by turning clockwise. Moreover, one drive output 1724 b or1724 e,f may lag or precede the other, depending on the mechanism lag orslop. Accordingly, such control algorithms may be used to compensate,reduce lag, and reduce slack for one or more of the drive inputs 1636a-d (FIGS. 16 and 17B).

Referring again to FIG. 19, with continued reference to FIG. 20, toarticulate the end effector 1604 clockwise C₂, the first drive member1816 a is moved proximally and the second drive member 1816 b is moveddistally. In such operation, the first drive member 1816 a may be movedproximally a greater distance than the second drive member 1816 b ismoved distally, which allows the second drive member 1816 b to maintainpull tension as it travels less than the first drive member 1816 a,which helps reduce lag and/or slop. To articulate the end effector 1604counter clockwise C₁, the second drive member 1816 b is moved proximallyand the first drive member 1816 a is moved distally. In such operation,the second drive member 1816 b is moved proximally a greater distancethan the first drive member 1816 a is moved distally, which allows thefirst drive member 1816 a to maintain pull tension as it travels lessthan the second drive member 1816 b, which also helps reduce lag and/orslop.

FIGS. 21A and 21B are enlarged isometric top and bottom views,respectively, of an example carriage 2100, according to one or moreembodiments. The carriage 2100 may be similar in some respects to thecarriage 1626 of FIGS. 16 and 18A-18C and therefore may be bestunderstood with reference thereto. In some applications, the carriage2100 may replace the carriage 1626 in the drive housing 1614 of FIG. 16.As illustrated, the carriage may comprise two or more layers, shown inFIGS. 21A-21B as a first layer 2102 a, a second layer 2102 b, a thirdlayer 2102 c, and a fourth layer 2102 d. While four layers 2102 a-e aredepicted, more or less than four may be included in the carriage 2100,without departing from the scope of the disclosure. The shaft 1602 iscoupled to and extends distally from the carriage 2100, and the carriage2100 is able to translate along the longitudinal axis A₁ by moving upand down (traversing) the lead screw 1622, as generally described abovewith reference to FIG. 16. As the carriage 2100 moves along thelongitudinal axis A₁, the end effector 1604 (FIG. 16) correspondinglyadvances or retracts.

In the illustrated embodiment, the carriage 2100 includes an activatingmechanism 2104 operable to articulate the end effector 1604 at the wrist1606 (FIGS. 16 and 19). The activating mechanism 2104 may be similar insome respects to the second activating mechanism 1638 b (FIGS. 16 and18A-18C) and may be actuated through rotation of the second spline 1624b. In the illustrated embodiment, the second spline 1624 b isoperatively coupled to the activating mechanism 2104 such that rotatingthe second spline 1624 b (e.g., via rotation of the third drive input1636 c of FIGS. 16 and 17B) correspondingly actuates the activatingmechanism 2104 and thereby causes the wrist 1606 to articulate. Morespecifically, the drive gear 1806 is included with the second spline1624 b and positioned to intermesh with a driven gear 2106 coupled to orotherwise forming part of an articulation barrel 2108. As the spline1624 b is rotated, the drive gear 1806 drives the driven gear 2106 andcorrespondingly rotates the articulation barrel 2108 about thelongitudinal axis A₁.

The articulation barrel 2108 defines or otherwise provides one or morecam slots or profiles, partially shown in FIGS. 21A-21B as a first camprofile 2110 a (FIG. 21A) and a second cam profile 2110 b (FIG. 21B).The activating mechanism 2104 further includes a first follower pin 2112a (FIG. 21A) and a second follower pin 2112 b (FIG. 21B). The firstfollower pin 2112 a extends through the first cam profile 2110 a and iscoupled to a first carrier 2114 a (FIG. 21A), and the second followerpin 2112 b extends through the second cam profile 2110 b and is coupledto a second carrier 2114 b (FIG. 21B). Each cam profile 2110 a,b extendsabout the circumference of the articulation barrel 2108 (e.g., in ahelical pattern), but the profiles are defined at opposite angles.

As the drive gear 1806 drives the driven gear 2106, the articulationbarrel 2108 correspondingly rotates about the longitudinal axis A₁, thusurging the follower pins 2112 a,b to traverse the oppositely-angled camprofiles 2110 a,b, respectively. As the follower pins 2112 a,b traversethe cam profiles 2110 a,b, the underlying carriers 2114 a,b are urged inequal but opposite axial directions along the longitudinal axis A₁.Depending on the rotation direction of the drive gear 1806, the carriers1814 a,b may be drawn axially toward each other or moved axially awayfrom each other.

In some embodiments, as illustrated, the activating mechanism 2104 mayfurther include a first articulation torque bar 2116 a (FIG. 21A) and asecond articulation torque bar 2116 b (FIG. 21B). The articulationtorque bars 2116 a,b may be secured to the carriage 2100 using one ormore mechanical fasteners 2118 (e.g., screws, bolts, etc.). In theillustrated embodiment, the articulation bars 2116 a,b extend betweenthe second and third layers 2102 b,c and may be secured to each layer2102 b,c at each end. Each torque articulation bar 2116 a,b may define aslot 2120 sized to receive the head of the corresponding follower pin2112 a,b. During actuation/operation of the activating mechanism 2104,the articulation torque bars 2116 a,b may help maintain an axialposition of the corresponding follower pin 2112 a,b. More specifically,as the articulation barrel 2108 rotates, the follower pins 2112 a,b willhave a tendency to also rotate as they traverse the corresponding camprofiles 2110 a,b. Receiving the head of each follower pin 2112 a,bwithin the slots 2120 of each stationary articulation torque bar 2116a,b will help prevent the follower pins 2112 a,b from rotating butinstead maintain their axial position.

FIGS. 22A and 22B are isometric top and bottom views, respectively, of aportion of the activation mechanism 2104, according to one or moreembodiments. Many component parts of the carriage 2100 are omitted inFIGS. 22A-22B to enable a fuller view of various parts of the activationmechanism 2104. As illustrated, the articulation barrel 2108 maycomprise a generally cylindrical structure that extends about the shaft1602 and, more particularly, about the inner grounding shaft 1810. Thefirst and second carriers 2114 a,b interpose the inner grounding shaft1810 and the articulation barrel 2108 and are independently movablealong the longitudinal axis A₁. The first carrier 2114 a may beoperatively coupled to the first drive member 1816 a (FIG. 22A), whichextends distally to the wrist 1606 (FIG. 16) at least partially withinthe slot 1818 defined in the inner grounding shaft 1810. Moreover, thesecond carrier 2114 b may be operatively coupled to the second drivemember 1816 b (FIG. 22B), which extends distally to the wrist 1606 atleast partially within the slot 1820 defined in the inner groundingshaft 1810.

The follower pins 2112 a,b extend through the corresponding cam profiles2110 a,b and are coupled to the associated carriers 2114 a,b,respectively. In some embodiments, one or both of the follower pins 2112a,b may be made of or coated with a lubricious material configured tobear against the inner walls of the cam profiles 2110 a,b as thearticulation barrel 2108 rotates, thus reducing friction. In otherembodiments, however, and as illustrated, one or both of the followerpins 2112 a,b may including one or more bearings, shown as a firstbearing 2202 a and a second bearing 2202 b. In the illustratedembodiment, the first and second bearings 2202 a,b are stacked on top ofeach other and the shaft of each follower pin 2112 a,b extends throughthe first and second bearings 2202 a,b. The first bearings 2202 a may beconfigured to bear against the inner walls of the cam profiles 2110 a,bas the articulation barrel 2108 rotates and the follower pins 2112 a,bare urged to traverse the cam profiles 2110 a,b, respectively, thusreducing friction. The second bearings 2202 b may be configured to bearagainst the inner walls of the slot 2120 (FIGS. 21A-21B) defined in thecorresponding torque articulation bar 2116 a,b (FIGS. 21A-21B) toprevent rotational movement of the follower pins 2112 a,b as thearticulation barrel 2108 rotates.

The articulation barrel 2108 has a first end 2204 a and a second end2204 b, and the driven gear 2106 may be defined or otherwise provided ator near the first end 2204 a, but could alternatively be provided at ornear the second end 2204 b or at any other another location between thefirst and second ends 2204 a,b. While actuating the activation mechanism2104, the drive gear 1806 drives the driven gear 2106 and therebyrotates the articulation barrel 2108 about the longitudinal axis A₁. Asthe articulation barrel 2108 rotates, the follower pins 2112 a,b areurged to traverse the cam profiles 2110 a,b, respectively, and theinterconnected carriers 2114 a,b are correspondingly urged in equal butopposite axial directions along the longitudinal axis A₁. As thecarriers 2114 a,b move axially, the interconnected drive members 1816a,b simultaneously move in the same direction and thereby cause the endeffector 1604 (FIGS. 16 and 19) to articulate, as described above.

In some embodiments, the cam profiles 2110 a,b may comprise straightslots extending at a constant angle about the circumference of thearticulation barrel 2108, but at opposite angular directions. If thefirst cam profile 2110 a extends at a positive angle relative to thelongitudinal axis A₁ (e.g., 15° or 75°), for example, then the secondcam profile 2110 b would extend at an equal but opposite negative anglerelative to the longitudinal axis A₁ (e.g., −15° or −75°). Inembodiments where the cam profiles 2110 a,b are straight, the movementand force applied to the carriers 2114 a,b and drive members 1816 a,bwill be constant during articulation of the end effector 1604 (FIGS. 16and 19). In such embodiments, the cam profiles 2110 a,b may becharacterized as helical cam slots and the follower pins 2112 a,b may becharacterized as linear cam followers.

In other embodiments, however, one or both of the cam profiles 2110 a,bmay not be entirely straight but may alternatively diverge at one ormore inflection points along the length (path) of the cam profile 2110a,b. More specifically, the cam profiles 2110 a,b may diverge fromstraight and define a more or less aggressive path 2206 (shown in dashedlines), depending on the direction at the inflection point. Higher orlower angles of the cam profiles 2110 a,b will alter the mechanicaladvantage obtained as the follower pins 2112 a,b traverse the camprofiles 2110 a,b and act on the interconnected carriers 2114 a,b,respectively. This may also prove advantageous in making the systemeasier to back-drive and put the end effector 1604 (FIGS. 16 and 19)back in line with the longitudinal axis A₁ in the event of a powerfailure.

In some embodiments, the ends of the cam profiles 2110 a,b may becharacterized or otherwise operate as physical stops detectable byvarious input torque sensors associated with the instrument driver 1702(FIGS. 17A-17B). In other embodiments, the ends of the cam profiles 2110a,b may be position controlled, which would provide extra traveldistance to compensate for tolerances, and thus minimize mechanismdamage if over shot slightly (e.g., no build up of loads).

FIG. 23 is a cross-sectional side view of the carriage 2100. Asillustrated, the first and second carriers 2114 a,b radially interposethe inner grounding shaft 1810 and the articulation barrel 2108, asmentioned above. Moreover, the first carrier 2114 a is operativelycoupled to or otherwise mated with the first drive member 1816 a, andthe second carrier 2114 b is operatively coupled to or otherwise matedwith the second drive member 1816 b. The follower pins 2112 a,b extendthrough the slots 2120 in the articulation torque bars 2116 a,b andcorresponding cam profiles 2110 a,b, respectively, to be coupled to theassociated carriers 2114 a,b. In some embodiments, the follower pins2112 a,b may be threaded to the corresponding carriers 2114 a,b, but mayalternatively be secured to the carriers 2114 a,b in other ways, such asthrough an interference (shrink) fit, welding, an adhesive, a snap fit,or any combination thereof. In other embodiments, the follower pins 2112a,b may be merely received within corresponding apertures defined in thecarriers 2114 a,b, and not necessarily fixed thereto, without departingfrom the scope of the disclosure.

As illustrated, the first bearings 2202 a bear against the inner wallsof the corresponding cam profiles 2110 a,b, and the second bearings 2202b are able to bear against the inner walls of the slot 2120 defined inthe corresponding torque articulation bars 2116 a,b. Placing the head ofthe follower pins 2112 a,b in the slots 2120 may help ensure that all ofthe motion of the interconnected carrier 2114 a,b is linear insteadrotational as the follower pins 2112 a,b traverse the cam profiles 2110a,b, respectively. Consequently, to negate lateral twisting of thefollower pins 2112 a,b, the follower pins 2112 a,b are received withinthe slots 2120, which restrict rotational movement of the follower pins2112 a,b.

While actuating the activation mechanism 2104, the drive gear 1806(FIGS. 21A-21B, 22A-22B) drives the driven gear 2106 and thereby rotatesthe articulation barrel 2108 about the longitudinal axis A₁. As thearticulation barrel 2108 rotates, the follower pins 2112 a,b are urgedto traverse the cam profiles 2110 a,b, respectively, and thecorresponding carriers 2114 a,b are urged in equal but opposite axialdirections along the longitudinal axis A₁ because of the oppositelyangled cam profiles 2110 a,b. Depending on the rotation direction of thedrive gear 1806, the carriers 2114 a,b may be drawn axially toward eachother or moved axially away from each other.

Opposite axial movement of the first and second carriers 2114 a,brelative to the inner grounding shaft 1810 correspondingly moves thedrive members 1816 a,b in the same opposite axial directions and,thereby, articulates the end effector 1604 (FIGS. 16 and 17B). In atleast one embodiment, the first and second carriers 2114 a,bantagonistically operate such that one of the carriers 2114 a,b pullsone of the drive members 1816 a,b proximally while the other carrier2114 a,b simultaneously pushes the other drive member 1816 a,b distally.As the carriers 2114 a,b are drawn axially toward each other, the endeffector 1604 will articulate in a first direction, and as the carriers2114 a,b are moved axially away from each other, the end effector 1604will articulate in a second direction opposite the first direction.

Firing Mechanism on Translating System

FIG. 24 is another enlarged isometric view of the carriage 1626 of FIG.16, and further provides an enlarged view of the third activatingmechanism 1638 c briefly described above. As mentioned above, the thirdspline 1624 c can be operatively coupled to the third activatingmechanism 1638 c such that rotating the third spline 1624 c (viarotation of the fourth drive input 1636 d of FIGS. 16 and 17B) willcorrespondingly actuate the third activating mechanism 1638 c andthereby cause the cutting element (knife) at the end effector 1604(FIGS. 16, 17B, 19) to “fire”. As discussed above, “firing” the endeffector 1604 refers to advancing or retracting the cutting element(knife), depending on the rotational direction of the third spline 1624c.

As illustrated, the third spline 1624 c extends longitudinally throughcoaxially aligned apertures 2402 defined in the fourth and fifth layers1628 d,e of the carriage 1626. A drive gear 2404 may be coupled to thethird spline 1624 c and configured to rotate as the third spline 1624 crotates. As illustrated, the drive gear 2404 may be located betweenadjacent portions of the fourth and fifth layers 1628 d,e. In someembodiments, the drive gear 2404 may comprise a separate component partdisposed about the third spline 1624 c and capable of translating(sliding) along the third spline 1624 c as the carriage 1626 moves alongthe longitudinal axis A₁. In other embodiments, however, the thirdspline 1624 c may be shaped and otherwise configured to operate as thedrive gear 2404 to advantageously reduce the number of component parts.

The drive gear 2404 may be configured to drive an input gear 2406 alsomounted to the carriage 1626 and forming part of the third activatingmechanism 1638 c. In some embodiments, the drive gear 2404 may bepositioned to directly intermesh with the input gear 2406 and therebydirectly drive the input gear 2406 as the third spline 1624 c rotates.In other embodiments, however, an idler gear 2408 may interpose thedrive gear 2404 and the input gear 2406 and may otherwise transfertorque from the drive gear 2404 to the input gear 2406 via anintermeshed gearing arrangement.

FIG. 25 is an enlarged view of the proximal end of the carriage 1626 andthe third activating mechanism 1638 c. Various parts of the carriage1626 are omitted in FIG. 25, such as the fifth layer 1628 e, to enable afuller view of the third activating mechanism 1638 c. As illustrated,the drive gear 2404 is coupled to or forms part of the third spline 1624c and intermeshes with the idler gear 2408, which correspondinglyintermeshes with the input gear 2406. In other embodiments, however, thedrive gear 2404 may alternatively directly contact and drive the inputgear 2406, without departing from the scope of the disclosure.

As described in more detail below, the input gear 2406 may be rotatablysecured to the carriage 1626 with a channel retainer 2502 (onlypartially visible), and the channel retainer 2502 may be axially fixedto the carriage 1626 with a locking mechanism 2504. In the illustratedembodiment, the locking mechanism 2504 is depicted as a c-ring or ane-ring, but may alternatively comprise any other device or mechanismcapable of axially fixing the channel retainer 2502 to the carriage1626.

The third activating mechanism 1638 c further includes a firing rod 2506longitudinally extendable through the carriage 1626. In at least oneembodiment, as illustrated, the firing rod 2506 may also extend at leastpartially through the input gear 2406. The firing rod 2506 extends alongthe longitudinal axis A₁ (FIG. 24) toward the end effector 1604 (FIGS.16, 17B, 19) and is operatively coupled to the cutting element (knife)such that longitudinal movement of the firing rod 2506 correspondinglymoves the knife in the same direction. In some embodiments, the firingrod 2506 extends to the end effector 1604 and directly couples to theknife. In other embodiments, however, the firing rod 2506 is coupled toa firing member (not shown) at some point between the carriage 1626 andthe end effector 1604, and the firing member extends to the end effector1604 to directly couple to the knife. In either scenario, actuation ofthe third activating mechanism 1638 c causes the knife to “fire”, i.e.,advance or retract, depending on the rotational direction of the thirdspline 1624 c.

FIG. 26 is an isometric, cross-sectional side view of the thirdactivating mechanism 1638 c, according to one or more embodiments. Asillustrated, the drive gear 2404 is intermeshed with the idler gear2408, which correspondingly intermeshes with the input gear 2406.Alternatively, as mentioned above, the drive gear 2404 may directlyintermesh with the input gear 2406.

The input gear 2406 may include or may otherwise be coupled to anelongate cylindrical body 2602 that has a first or “distal” end 2604 aand a second or “proximal” end 2604 b opposite the first end 2604 a. Asillustrated, the input gear 2406 is located at or near the second end2604 b. The elongate cylindrical body 2602 extends distally from theinput gear 2406 within the shaft 1602 and, more particularly, within theinner grounding shaft 1810, which is at least partially arranged withinthe closure tube 1812. The channel retainer 2502 also extends within theinner grounding shaft 1810 and helps rotatably secure the input gear2406 and the elongate cylindrical body 2602 to the carriage 1626. Asillustrated, the channel retainer 2502 may comprise a cylindrical membersized to receive the elongate cylindrical body 2602 within its interior.The channel retainer 2502 may be axially fixed to the carriage 1626 withthe locking mechanism 2504, which may be received within a groove 2606defined on the proximal end of the channel retainer 2502.

The channel retainer 2502 may provide or otherwise define an innerradial shoulder 2608 configured to engage the first end 2604 a of theelongate cylindrical body 2602 and thereby prevent the elongatecylindrical body 2602 from moving distally. At the second end 2604 b ofthe elongate cylindrical body 2602, the channel retainer 2502 bearsagainst one axial side (i.e., the distal end) of the input gear 2406,while one or more thrust bearings 2610 (three shown) bear against theopposite axial side (i.e., the proximal end) of the input gear 2406. Inone or more embodiments, the thrust bearings 2610 may be received withina pocket 2611 defined in the fifth layer 1628 e, and secured in place asthe fifth layer 1628 e is coupled to the fourth layer 1628 d.Consequently, the input gear 2406 is secured axially in place betweenthe channel retainer 2502 and the thrust bearings 2610 butsimultaneously allowed to rotate about the longitudinal axis A₁. Thethrust bearings 2610 may be configured to assume axial loading on theinput gear 2406 as the third activating mechanism 1638 c is actuated.The thrust bearings 2610 may also prove advantageous in reducingrotational friction of the input gear 2406 while driving (firing) thefiring rod 2506.

Some or all of the firing rod 2506 may provide or otherwise defineexternal threads 2612 configured to threadably engage internal threads2614 provided at or near the first end 2604 a of the elongatecylindrical body 2602. In example operation of the third activatingmechanism 1638 c, the third spline 1624 c is rotated (via rotation ofthe fourth drive input 1636 d of FIGS. 16 and 17B) and the drive gear2404 correspondingly rotates to drive the input gear 2406 (eitherdirectly or through the idler gear 2408). Rotating the input gear 2406correspondingly rotates the elongate cylindrical body 2602 in the sameangular direction, which drives the internal threads 2614 of the body2602 against the external threads 2612 of the firing rod 2506, andthereby advances or retracts the firing rod 2506 along the longitudinalaxis A₁, as indicated by the arrows D. Longitudinal movement of thefiring rod 2506 correspondingly moves the knife in the same direction atthe end effector 1604 (FIGS. 16, 17B, 19).

Referring to FIG. 27, with continued reference to FIG. 26, depicted isan enlarged cross-sectional view of the end effector 1604, according toone or more embodiments. As mentioned above, the end effector 1604includes opposing jaws 1610, 1612 movable between open and closedpositions, and the jaws 1610, 1612 are depicted in FIG. 27 in the openposition. The end effector 1604 may further include a knife 2702 thatcan be linearly displaced within the slot 1616 defined in the second jaw1610 to cut tissue grasped between the jaws 1610, 1612. As the knife2702 advances distally within the slot 1616, a sled or camming wedge2704 simultaneously engages a plurality of staples (not shown) containedwithin the first jaw 1610 (e.g., within a staple cartridge) and urges(cams) the staples into deforming contact with the opposing anvilsurfaces (e.g., pockets) provided on the second jaw 1612. Properlydeployed staples help seal opposing sides of the transected tissue.

As illustrated, the knife 2702 is operatively coupled to a firing member2706 that extends proximally (i.e., to the right in FIG. 27) and isoperatively coupled to the firing rod 2506 of FIGS. 25-26 at itsproximal end. In other embodiments, however, the knife 2702 may bedirectly coupled to the firing rod 2506, without departing from thescope of the disclosure. Actuation of the firing rod 2506, as generallydescribed above, causes the firing member 2706 to advance and retractand correspondingly advance and retract the knife 2702 so that it cantransect tissue grasped between the jaws 1610, 1612. Distal movement ofthe firing member 2706 also correspondingly moves the camming wedge 2704to deploy the staples, as described above.

In some embodiments, movement of the firing rod 2506 (FIGS. 25-26) inthe distal direction may also cause the jaws 1610, 1612 to close. Morespecifically, in one or more embodiments, the rod 2506 (or the firingmember 2706) or the knife 2702 may include a feature or structure (notshown) configured to engage an anvil 2708 provided on the upper jaw1612. In such embodiments, as the firing rod 2506 is advanced distally,the feature or structure will axially engage the angled surface of theanvil 2708 and force the second jaw 1612 to close. This approach iscommonly referred to as “knife-based” closure, and in such embodiments,the jaws 1610, 1612 may be spring biased to the open position when theknife 2702 is fully retracted. In other embodiments, however, as thefiring rod 2506 is advanced distally, the closure tube 1812 (FIG. 26)may be simultaneously advanced in the same direction to engage the anvil2708 and force the second jaw 1612 to close. This approach is commonlyreferred to as “tube-based” closure.

Clamping Mechanism on a Translating System

FIG. 28A is an enlarged isometric view of another embodiment of thecarriage 1626 of FIG. 16, and further provides an enlarged view of atleast one embodiment of the first activating mechanism 1638 a brieflydescribed above. As mentioned herein, the first activating mechanism1638 a may be actuated or otherwise activated to open or close the jaws1610, 1612 (FIGS. 16 and 17B) at the end effector 1604 (FIGS. 16 and17B). More specifically, the first spline 1624 a may be operativelycoupled to the first activating mechanism 1638 a such that rotating thefirst spline 1624 a (via rotation of the second drive input 1636 b ofFIGS. 16 and 17B) will correspondingly actuate the first activatingmechanism 1638 a and thereby open or close the jaws 1610, 1612,depending on the rotational direction of the first spline 1624 a.

As illustrated, the first spindle 1624 a extends longitudinally throughcoaxially aligned apertures 2802 (only one visible) defined in the firstand second layers 1628 a,b of the carriage 1626. A drive gear 2804 maybe included with the first spindle 1624 a and located between adjacentportions of the first and second layers 1628 a,b. The first spindle 1624a may exhibit a cross-sectional shape matable with a corresponding innershape of the drive gear 2804 such that rotation of the first spindle1624 a correspondingly drives the drive gear 2804 in rotation. In someembodiments, the drive gear 2804 may comprise a separate component partslidably disposed about the outer surface of the first spindle 1624 a.In such embodiments, as the carriage 1626 moves along the longitudinalaxis A₁ (FIG. 16), the drive gear 2804 will correspondingly move alongthe length of the first spindle 1624 a as captured between the first andsecond layers 1628 a,b. In such embodiments, the apertures 2802 mayinclude or otherwise define bearing surfaces (e.g., between the face ofthe drive gear 2804 and the layers 1628 a,b and/or between an outerdiameter collar of the drive gear 2804 and the inner diameter of theapertures 2820) to help reduce friction as the carriage 1626 traversesthe first spindle 1624 a. In other embodiments, however, the firstspindle 1624 a may be shaped and otherwise configured to operate as adrive gear. In such embodiments, the drive gear 2804 may be omitted toadvantageously reduce the number of component parts.

The first activating mechanism 1638 a may include a driven gear 2806,and the drive gear 2804 may be positioned on the carriage 1626 to engageor otherwise intermesh with the driven gear 2806. In other embodiments,however, one or more intermediate gears (e.g., idler gears) mayinterpose the drive gear 2804 and the driven gear 2806. Accordingly, asthe first spline 1624 a is rotated, the drive gear 2804 is able to drivethe driven gear 2806 in rotation and thereby actuate the firstactivating mechanism 1638 a. As illustrated, the driven gear 2806 mayalso be located between adjacent portions of the first and second layers1628 a,b of the carriage 1626.

The first activating mechanism 1638 a may further include a key 2808(shown in dashed lines) provided or otherwise defined on the outersurface of the shaft 1602 and, more particularly, on the outer surfaceof the closure tube 1812 of the shaft 1602. The key 2808 may be receivedwithin a slot 2810 defined in the carriage 1626 and, more particularly,in the first layer 1628 a. In the illustrated embodiment, the key 2808is depicted as an elongate member or protrusion, and the slot 2810 maydefine an opening sized to receive the key 2808. Actuating the firstactivating mechanism 1638 a causes the closure tube 1812 to translatealong the longitudinal axis A₁, which correspondingly causes the key2808 to translate longitudinally within the slot 2810. With the key 2808received within the slot 2810, the closure tube 1812 is prevented fromrotating during longitudinal movement of the closure tube 1812 resultingfrom actuation of the first activating mechanism 1638 a.

FIG. 28B is an enlarged isometric view of the first activating mechanism1638 a, according to one or more embodiments. Various parts of thecarriage 1626, including the first and second layers 1626 a,b (FIG.28A), are omitted in FIG. 28B to enable a fuller view of the firstactivating mechanism 1638 a. As illustrated, the driven gear 2806 maycomprise an annular structure that extends about the closure tube 1812of the shaft 1602, and the key 2808 is depicted as coupled to orotherwise defined on the outer surface of the closure tube 1812.Moreover, the gear teeth of the driven gear 2806 intermesh with gearteeth of the drive gear 2804 to enable the drive gear 2804 to rotate thedriven gear 2806 when the first spline 1624 a is rotated.

The first activating mechanism 1638 a may further include a carrier 2812arranged at the proximal end of the closure tube 1812. The driven gear2806 is internally threaded and configured to threadably engage externalthreads defined by the carrier 2812. Consequently, as the drive gear2804 rotates, the driven gear 2806 correspondingly rotates and moves theclosure tube 1812 along the longitudinal axis A₁ (FIG. 28A) via thethreaded engagement between the driven gear 2806 and the carrier 2812.Depending on the rotation direction of the drive gear 2804, the closuretube 1812 may be driven distally (i.e., to the left in FIG. 28B) orproximally (i.e., to the right in FIG. 28B).

In some embodiments, the carrier 2812 may form an integral part of theclosure tube 1812 and thereby constitute the proximal end of the shaft1602. In such embodiments, the proximal end of the shaft 1602 may bethreaded to form the carrier 2812. In other embodiments, however, thecarrier 2812 may comprise a separate component part arranged at theproximal end of the closure tube 1812. In such embodiments, the carrier2812 may be configured to receive the proximal end of the closure tube1812 and may radially interpose a portion of the closure tube 1812 andthe driven gear 2806. In either scenario, movement of the carrier 2812along the longitudinal axis A₁ (FIG. 28A), will correspondingly move theclosure tube 1812 in the same axial direction.

FIG. 28C is an isometric, cross-sectional side view of the firstactivating mechanism 1638 a, according to one or more embodiments. Inthe illustrated embodiment, the carrier 2812 comprises a separatecomponent part arranged at a proximal end 2814 of the closure tube 1812and radially interposes a portion of the closure tube 1812 and thedriven gear 2806. In such embodiments, the carrier 2812 may define aninner radial shoulder 2816 engageable with the proximal end 2814 of theclosure tube 1812. As mentioned above, however, the carrier 2812 mayalternatively form an integral part of the closure tube 1812 at theproximal end 2814, without departing from the scope of the disclosure.

The driven gear 2806 defines internal threading 2818 a matable withexternal threading 2818 b defined on the outer surface of the carrier2812. As the driven gear 2806 is driven to rotate about the longitudinalaxis A₁, the threaded engagement between the internal and externalthreadings 2818 a,b causes the carrier 2812 to axially advance orretract along the longitudinal axis A₁, and correspondingly advance orretract the closure tube 1812 in the same axial direction. As thecarrier 2812 advances distally (i.e., to the left in FIG. 28C), theinner radial shoulder 2816 bears against the proximal end 2814 of theclosure tube 1812 and thereby forces the closure tube 1812 in the samedistal direction. Advancing the closure tube 1812 distally forces thejaws 1610, 1612 (FIGS. 16 and 17B) to close, and retracting the closuretube 1812 proximally (i.e., to the right in FIG. 28C) allows the jaws1610, 1612 to open.

In some embodiments, the thread pitch of the internal and externalthreadings 2818 a,b and/or the gear ratio between the drive and drivengears 2804, 2806 may be altered or otherwise optimized to change loadand speed needs for moving the closure tube 1812. This may proveadvantageous since jaw closing typically has two functions: 1) graspingtissue for manipulation, which may require more precision movements(e.g., low load, speed control, precision, etc.), and 2) applying thetissue compression requirement to transect tissue and form staples(e.g., high load). The speed of the last stage of compression is key forthe stabilization of the tissue as the fluid in the tissue is evacuatedand compression is optimized for stapling and transection. Accordingly,the speed of compression should be slow, and slower than general motionof a jaw closing in the air. Moreover, as the closure tube 1812 advancesor retracts, the key 2808 will slidably engage the slot 2810 (FIG. 28A)defined in the first layer 1628 a (FIG. 28A) of the carriage 1626 (FIG.28A) and thereby prevent the closure tube 1812 from rotating whilemoving longitudinally. This may be advantageous allowing only axialtranslation of the closure tube 1812 as the first activating mechanism1638 a is actuated.

Referring to FIG. 29, with continued reference to FIG. 28C, depicted isan enlarged view of the end effector 1604 and the wrist 1606, accordingto one or more embodiments. As illustrated, the wrist 1606 may include afirst or “proximal” clevis 2902 a, a second or “distal” clevis 2902 b,and a closure link 2904 configured to operatively couple the proximaland distal devises 2902 a,b across the wrist 1606. The proximal clevis2902 a may be coupled to or otherwise form part of the distal end of theclosure tube 1812, and the distal clevis 2902 b may be coupled to orotherwise form part of a closure ring 2906.

Axial movement of the closure tube 1812 along the longitudinal axis A₁,as generally described above, correspondingly moves the proximal clevis2902 a in the same axial direction, and the closure link 2904 isconfigured to transmit the axial load through (across) the wrist 1606 toclose the jaws 1610, 1612 of the end effector 1604. More specifically,the closure link 2904 defines a pair of protrusions 2908 configured tomate with corresponding apertures 2910 defined in each of the proximaland distal devises 2902 a,b. The closure link 2904 may transmit theclosure load or translation of the closure tube 1812 from the distalclevis 2902 b to the proximal clevis 2902 a and the closure ring 2906will correspondingly push or pull on the upper jaw 1612 to open or closethe upper jaw 1612. To close the upper jaw 1612, the closure ring 2906is forced against a shoulder 2912 at or near the back of the upper jaw1612, which urges the upper jaw 1612 to pivot down and to the closedposition. To open the upper jaw 1612, the closure ring 2906 is retractedproximally by retracting the closure tube 1812, and the closure ring2906 helps pull the upper jaw 1612 back toward the open position.Alternatively, the upper jaw 1612 may be spring loaded and biased to theopen position, and retracting the closure ring 2906 removes loading onthe shoulder 2912, which allows the spring force to move the upper jaw1612 to the open position.

FIG. 30A is an enlarged isometric top view of the carriage 2100 of FIGS.21A-21B, according to one or more additional embodiments. In theillustrated embodiment, the carriage 2100 includes an activatingmechanism 3002 similar in some respects to the first activatingmechanism 1638 a of FIGS. 28A-28C. Similar to the first activatingmechanism 1638 a, for example, the activating mechanism 3002 may beactuated through rotation of the first spline 1624 a and is operable toopen or close the jaws 1610, 1612 (FIGS. 16, 17B, and 29) of the endeffector 1604 (FIGS. 16, 17B, and 29). More specifically, the firstspline 1624 a may be operatively coupled to the activating mechanism3002 such that rotating the first spline 1624 a (e.g., via rotation ofthe second drive input 1636 b of FIGS. 16 and 17B) correspondinglyactuates the activating mechanism 3002 and thereby causes the closuretube 1812 of the shaft 1602 to advance or retract along the longitudinalaxis A₁.

The activating mechanism 3002 includes a driven gear 3004, and the drivegear 2804 of the first spline 1624 a may be positioned to intermesh withthe driven gear 3004 such that rotation of the drive gear 2804 willcorrespondingly rotate the driven gear 3004 in the same direction. Asillustrated, the driven gear 3004 may be coupled to or otherwise formpart of a closure barrel 3006. As the spline 1624 b is rotated, thedrive gear 2804 drives the driven gear 3004 and causes the closurebarrel 3006 to rotate about the longitudinal axis A₁.

The closure barrel 3006 may be positioned in the carriage 2100 betweenthe first and second layers 2102 a,b. One or more thrust bearings may bearranged at one or both axial ends of the closure barrel 3006 to helpassume axial loading on the closure barrel 3006 as the activatingmechanism 3002 operates. In the illustrated embodiment, one or morefirst thrust bearings 3008 a (one shown) are arranged at the distal endof the closure barrel 3006 and may interpose the closure barrel 3006 andthe first layer 2102 a. In one or more embodiments, one or moreadditional thrust bearings (not shown) may be arranged at the proximalend of the closure barrel 3006 and interpose the closure barrel 3006 anda portion of the second layer 2102 b, without departing from the scopeof the disclosure. The thrust bearings 3008 a may prove advantageous inreducing rotational friction as the closure barrel 3006 rotates.

The activating mechanism 3002 may further include the key 2808 (shown indashed lines) provided or otherwise defined on the outer surface of theclosure tube 1812. The key 2808 may be received within a slot 3010defined in the first layer 2102 a of the carriage 2100. Actuating theactivating mechanism 3002 causes the closure tube 1812 to translatealong the longitudinal axis A₁, which correspondingly causes the key2808 to translate longitudinally within the slot 3010 and thereby helpprevent the closure tube 1812 from rotating during longitudinal movementof the closure tube 1812.

FIG. 30B is an enlarged isometric view of the activating mechanism 3002,according to one or more embodiments. Various component parts of thecarriage 2100 are omitted in FIG. 30B, such as the first layer 2102 a(FIG. 30A), to enable a fuller view of various parts of the activationmechanism 3002. As illustrated, the closure barrel 3006 may comprise agenerally cylindrical structure that extends about the shaft 1602 and,more particularly, about the closure tube 1812. The closure barrel 3006defines or otherwise provides one or more cam slots or profiles, shownin FIG. 30B as a first cam profile 3014 a and a second cam profile 3014b. Each cam profile 3014 a,b extends a distance about the circumferenceof the closure barrel 3006 (e.g., in a generally helical pattern). Whilethe closure barrel 3006 provides two cam profiles 3014 a,b, it iscontemplated herein to only include one cam profile, without departingfrom the scope of the disclosure.

As illustrated, the activating mechanism 3002 further includes a firstfollower pin 3016 a and a second follower pin 3016 b. The first andsecond follower pins 3016 a,b extend through the first and second camprofiles 3014 a,b, respectively, and are operatively coupled (directlyor indirectly) to the proximal end of the closure tube 1812. In theillustrated embodiment, the first and second follower pins 3016 a,b areeach coupled to a carrier 3018 arranged at the proximal end of theclosure tube 1812. In some embodiments, the carrier 3018 may form anintegral part of the closure tube 1812 and thereby constitute theproximal end of the closure tube 1812. In other embodiments, however,the carrier 3018 may comprise a separate component part arranged at theproximal end of the closure tube 1812. In such embodiments, the carrier3018 may be configured to receive the proximal end of the closure tube1812 and may radially interpose a portion of the closure tube 1812 andthe closure barrel 3006. In either scenario, movement of the carrier3018 along the longitudinal axis A₁, will correspondingly move theclosure tube 1812 in the same axial direction.

As the drive gear 2804 drives the driven gear 3004, the closure barrel3006 correspondingly rotates about the longitudinal axis A₁, thus urgingthe follower pins 3016 a,b to traverse the cam profiles 3014 a,b,respectively. As the follower pins 3016 a,b traverse the cam profiles3014 a,b, the carrier 3018 is moved along the longitudinal axis A₁ andthe closure tube 1812 is urged in the same axial direction. Depending onthe rotation direction of the drive gear 2804, the carrier 3018 and theclosure tube 1812 may be moved distally (i.e., to the left in FIG. 30B)or proximally (i.e., to the right in FIG. 30B) and thereby close or openthe jaws 1610, 1612 (FIGS. 16, 17B, and 29) of the end effector 1604(FIGS. 16, 17B, and 29).

In some embodiments, as illustrated, one or both of the follower pins3016 a,b may including one or more bearings 3020 (one visible), and theshaft of each follower pin 3016 a,b extends through the bearings 3020.The bearings 3020 may be configured to bear against the inner walls ofthe cam profiles 3014 a,b as the closure barrel 3006 rotates and thefollower pins 3016 a,b traverse the cam profiles 3014 a,b, respectively.The bearings 3020 help reduce friction during actuation. Alternatively,or in addition thereto, one or both of the follower pins 3016 a,b mayexhibit a surface finish or include a coating that reduces friction. Inat least one embodiment, for instance, one or both of the follower pins3016 a,b may be coated with a lubricant or lubricious substance, such aspolytetrafluoroethylene (PTFE or TEFLON®) or an ultrahigh molecularweight (UMHL) polymer.

FIG. 30C is a cross-sectional side view of a portion of the carriage2100 and the activation mechanism 3002. As illustrated, the closurebarrel 3006 is positioned between the first and second layers 2102 a,b.The first thrust bearing 3008 a is arranged at the distal end of theclosure barrel 3006 and interpose the closure barrel 3006 and the firstlayer 2102 a, and one or more second thrust bearings 3008 b (one shown)may be arranged at the proximal end of the closure barrel 3006 andinterpose the closure barrel 3006 and a portion of the second layer 2102b. The thrust bearings 3008 a,b help assume axial loading on the closurebarrel 3006 and reduces rotational friction as the closure barrel 3006rotates.

In the illustrated embodiment, the carrier 3018 comprises a separatecomponent part arranged at a proximal end 3022 of the closure tube 1812and radially interposes a portion of the closure tube 1812 and theclosure barrel 3006. In such embodiments, the carrier 3018 may define aninner radial shoulder 3024 engageable with the proximal end 3022 of theclosure tube 1812. As mentioned above, however, the carrier 3028 mayalternatively form an integral part of the closure tube 1812 at theproximal end 3022.

The follower pins 3016 a,b extend through the corresponding cam profiles3014 a,b, respectively, to be coupled to the carrier 3018. In someembodiments, the follower pins 3016 a,b may be threaded to thecorresponding carrier 3018, but may alternatively be secured to thecarrier 3018 in other ways, such as through an interference (shrink)fit, welding, an adhesive, a snap fit, or any combination thereof. Inother embodiments, the follower pins 3016 a,b may be merely receivedwithin corresponding apertures defined in the carrier 3018, and notnecessarily fixed thereto, without departing from the scope of thedisclosure. As illustrated, the bearings 3020 are able to bear againstthe inner walls of the corresponding cam profiles 3014 a,b.

While actuating the activation mechanism 3002, the drive gear 2804(FIGS. 30A-3B) drives the driven gear 3004 and thereby rotates theclosure barrel 3006 about the longitudinal axis A₁. As the closurebarrel 3006 rotates, the follower pins 3016 a,b traverse the camprofiles 3014 a,b, respectively, and the carrier 3018 and the closuretube 1812 are correspondingly urged to move axially along thelongitudinal axis A₁. Depending on the rotation direction of the drivegear 2804, the carrier 3018 and the closure tube 1812 may be moveddistally (i.e., to the left in FIG. 30C) or proximally (i.e., to theright in FIG. 30C) and thereby close or open the jaws 1610, 1612 (FIGS.16, 17B, and 29) of the end effector 1604 (FIGS. 16, 17B, and 29).Moreover, as the closure tube 1812 advances or retracts, the key 2808will slidably engage the slot 3010 defined in the first layer 2102 a ofthe carriage 2100 and thereby prevent the closure tube 1812 fromrotating. This may be advantageous in preventing the closure tube 1812from rotating and only allowing axial translation of the closure tube1812 as the activating mechanism 3002 is actuated.

FIG. 31 is an isometric view of an example embodiment of the closurebarrel 3006, according to one or more embodiments. Each cam profile 3014a,b may comprise a slot that extends generally helically about a portionof the circumference of the closure barrel 3006. Accordingly, the camprofiles 3014 a,b may be characterized as helical cam slots and thefollower pins 3016 a,b may be characterized as linear cam followers. Thecam profiles 3014 a,b may prove advantageous in making the system easierto back-drive and open or close the jaws 1610, 1612 (FIGS. 16, 17B, and29) manually, as needed.

In some embodiments, each cam profile 3014 a,b may comprise a straightslot extending helically at a constant angle or slope about thecircumference of the closure barrel 3006. In such embodiments, themovement and force applied to the carrier 3018 and converted into anaxial load on the closure tube 1812 (FIGS. 30A-30C) will be constantduring actuation of the activation mechanism 3002 (FIGS. 30A-30C).

In other embodiments, however, one or both of the cam profiles 3014 a,bmay not be entirely straight but may alternatively diverge at one ormore inflection points 3102 along the helical length (path) of the camprofile 3014 a,b. More specifically, at the inflection point 3102, thecam profiles 3014 a,b may change from extending a first distance aboutthe circumference of the closure barrel 3006 at a first slope 3104 a toa second distance at a second slope 3104 b, where the second slope 3104b comprises a more or less aggressive path as compared to the firstslope 3104 a. A higher or lower angle or slope of the cam profile 3014a,b will correspondingly alter the mechanical advantage obtained as thefollower pins 3016 a,b traverse the cam profiles 3014 a,b and act on theinterconnected carrier 3018. This can result in higher axial loads beingapplied to the closure tube 1812 (FIGS. 30A-30B), which allows the jaws1610, 1612 (FIGS. 16, 17B, and 29) to clamp down with enhanced forcewhen needed. More particularly, and as mentioned above, jaw closingfunctions to grasp tissue for manipulation, which may require moreprecision movements, and applying compressive forces to the tissue,which requires higher loads. The varying slopes 3104 a,b may help thejaws 1610, 1612 operate more effectively, as needed.

Translation Through Tool Drive

FIG. 32 is another enlarged isometric view of the carriage 1626 of FIG.16. As discussed with reference to FIG. 16, the shaft 1602 is coupled toand extends distally from the carriage 1626 and penetrates the first end1618 a (FIG. 16) of the drive housing 1614 (FIG. 16). Moreover, thecarriage 1626 is movable between the first and second ends 1618 a,b(FIG. 16) along the longitudinal axis A₁ to advance or retract the endeffector 1604 (FIG. 16) relative to the drive housing 1614, as indicatedby the arrows B (i.e., z-axis translation).

In one or more embodiments, as briefly discussed above, axialtranslation of the carriage 1626 may be accomplished through the use andmechanical interaction of the lead screw 1622 and the carriage nut 1634.As illustrated, the carriage 1626 may be at least partially mounted tothe lead screw 1622 by having the lead screw 1622 extend through one ormore portions of the carriage 1626, such as adjacent portions of thethird and fourth layers 1628 c,d. In the illustrated embodiment, thelead screw 1622 extends through co-axially aligned apertures 3202 (onlyone shown) defined in adjacent portions of the third and fourth layers1628 c,d.

The carriage 1626 is configured to traverse the axial length of the leadscrew 1622 by mechanical interaction with the carriage nut 1634. Moreparticularly, the outer surface of the lead screw 1622 defines outerhelical threading and the carriage nut 1634 defines correspondinginternal helical threading (not shown) matable with the outer helicalthreading of the lead screw 1622. The carriage nut 1634 is immovablysecured to the carriage 1626 such that rotation of the lead screw 1622causes the carriage nut 1634 to convert the rotational force of the leadscrew 1622 into an axial load applied to the carriage 1626.Consequently, the carriage nut 1634 is urged to traverse the outerhelical threading of the lead screw 1622 and thereby advance or retractthe carriage 1626 along the longitudinal axis A₁ in the direction(s) B.As the carriage 1626 moves along the longitudinal axis A₁, the endeffector 1604 (FIG. 16) correspondingly advances or retracts relative tothe drive housing 1614. Depending on the rotational direction of thelead screw 1622, the carriage 1626 and the end effector 1604 may bemoved distally (i.e., to the left in FIG. 32) or proximally (i.e., tothe right in FIG. 32).

In some embodiments, the outer helical threading of the lead screw 1622may be uniform (constant) along the entire length of the lead screw1622. In such embodiments, the outer helical threading will be provided(defined) at a single common pitch between both ends of the lead screw1622. In other embodiments, however, the pitch of the outer helicalthreading may vary along portions of the lead screw 1622. Asillustrated, for example, a first portion 3204 a of the lead screw 1622may provide outer helical threading defined at a first pitch, while asecond portion 3204 b of the lead screw 1622 may provide outer helicalthreading defined at a second pitch different from the first pitch. Inthe illustrated embodiment, the second pitch defined on the secondportion 3204 b is more aggressive as compared to the first pitch definedon the first portion 3204 a. As a result, while the lead screw 1622 isrotated at a constant speed, the carriage 1626 will move along thelongitudinal axis A₁ at a faster speed while traversing the secondportion 3204 b as compared to traversing the first portion 3204 a. Thismay prove advantageous in allowing the operator to advance the endeffector (FIG. 16) toward a surgical site faster along select portionsof the lead screw 1622.

The lead screw 1622 may be made of a variety of rigid materialsincluding, but not limited to, a plastic (e.g., an extruded polymer), ametal (e.g., aluminum, stainless steel, brass, etc.), a compositematerial (e.g., carbon fiber, fiberglass, etc.), or any combinationthereof. The lead screw 1622 may exhibit a surface finish or include acoating that reduces friction against the carriage nut 1634 when thecarriage 1626 is under loading, i.e., twisting or compressive loads. Inat least one embodiment, for instance, the outer helical threading ofthe lead screw 1622 may be coated with a lubricant or lubricioussubstance 3205, such as polytetrafluoroethylene (PTFE or TEFLON®), ormay otherwise comprise an anodized surface.

In some embodiments, as illustrated, the carriage nut 1634 may comprisea separate component part mounted to the lead screw 1622 and secured tothe carriage 1626, such as between adjacent portions of the third andfourth layers 1628 c,d. In such embodiments, the carriage nut 1634 mayprovide or otherwise define an anti-rotation feature 3206 matable with acorresponding feature 3208 defined on the carriage 1626. Theanti-rotation feature 3206 may be configured to transfer rotationalloading assumed by the carriage nut 1634 through rotation of the leadscrew 1622 to the carriage 1626. As a result, the rotational loading canbe converted into axial loading that helps move the carriage 1626 alongthe longitudinal axis A₁. In the illustrated embodiment, theanti-rotation feature 3206 comprises a flange and the feature 3208comprises a pocket or recess configured to receive the flange.

In other embodiments, however, the carriage nut 1634 may form anintegral part of the carriage 1626. In such embodiments, one or both ofthe third and fourth layers 1628 c,d may operate as the carriage nut1634. More specifically, the carriage nut 1634 may be arranged withinone or both of the co-axially aligned apertures 3202, as indicated bythe dashed box 3210. Alternatively, one or both of the co-axiallyaligned apertures 3202 may be internally threaded to mate with the outerhelical threading of the lead screw 1622. In such embodiments, rotationof the lead screw 1622 will correspondingly drive the carriage 1626distally or proximally as threadably interacting with the threadedaperture(s) 3202.

FIGS. 33A and 33B are opposing isometric end views of the carriage nut1634, according to one or more embodiments. As illustrated, the carriagenut 1634 provides a generally cylindrical body 3302 having a first end3304 a and a second end 3304 b opposite the first end 3304 a. A centralconduit 3306 may be defined in the body 3302 and extend between thefirst and second ends 3304 a,b. As illustrated, internal helicalthreading 3308 may be defined on the inner wall of the central conduit3306 and may be configured to threadably mate with the external helicalthreading defined on the lead screw 1622 (FIG. 32).

In some embodiments, one or both of the ends 3304 a,b may provide orotherwise define the anti-rotation feature 3206 configured to preventthe carriage nut 1634 from rotating while traversing the lead screw(FIG. 32). In the illustrated embodiment, the anti-rotation feature 3206is provided at the second end 3304 b, but could alternatively beprovided at the first end 3304 a or both ends 3304 a,b. Once theanti-rotation feature 3206 is received within the corresponding feature3208 (FIG. 32) defined on the carriage 1626 (FIG. 32), the carriage nut1634 will be prevented from rotating relative to the carriage 1626,which allows the rotational force from the lead screw 1622 to betransferred through the carriage nut 1634 to the carriage 1626 in theform of an axial load that causes axial movement of the carriage 1626.

FIGS. 34A and 34B are isometric views of the first and second ends 1618a,b, respectively, of the drive housing 1614 of FIG. 16, according toone or more embodiments. The lead screw 1622 extends between and isrotatably mounted to the first and second ends 1618 a,b of the drivehousing 1614. More specifically, a first or “distal” end 3402 a (FIG.34A) of the lead screw 1622 is rotatably mounted to the first end 1618 aof the drive housing 1614, and a second or “proximal” end 3402 b (FIG.34B) of the lead screw 1622 is rotatably mounted to the second end 1618b of the drive housing 1614. Each end 3402 a,b of the lead screw 1622 isaxially supported at the first and second ends 1618 a,b, respectively tohelp prevent (minimize) linear movement of the lead screw 1622, whilesimultaneously allowing unrestricted rotational movement.

Referring to FIG. 34A, a driven gear 3404 is provided at or otherwiseforms part of the distal end 3402 a of the lead screw 1622. The drivengear 3404 is arranged to intermesh with a drive gear 3406 rotatablymounted at the first end 1618 a of the drive housing 1614. The drivegear 3406 may form part of or may otherwise be operatively coupled tothe first drive input 1636 a (FIGS. 16 and 17B) such that rotation ofthe first drive input 1636 a (via the first drive output 1724 a of theinstrument driver 1702 of FIGS. 17A-17B) correspondingly rotates thedriven gear 3404, which causes rotation of the lead screw 1622. In otherembodiments, the driven gear 3404 may be driven by a combination of thefirst drive input 1636 a and at least one additional drive input (notshown). Using an additional drive input may be required if the torsionalforces are high and can be distributed between two inputs. In at leastone embodiment, the first drive input 1636 a may comprise a direct inputinto the lead screw 1622 versus an arranged intermeshing of gears.

Referring to FIG. 34B, the proximal end 3402 b of the lead screw 1622may be rotatably mounted to the second end 1618 a of the drive housing1614. In some embodiments, one or more thrust bearings 3408 may bearranged at the proximal end 3402 b of the lead screw 1622 to reducerotational friction of the lead screw 1622 as it rotates.

FIG. 35 is another example of the drive housing 1614 of FIG. 16,according to one or more additional embodiments. As illustrated, thedrive housing 1614 includes the first and second ends 1618 a,b and thesplines 1624 a-c extending longitudinally between the first and secondends 1618 a,b. The carriage 1626 is movably mounted to the splines 1624a-c and the shaft 1602 extends distally from the carriage 1626 throughthe first end 1618 a of the drive housing 1614 and subsequently throughthe central aperture 1708 of the instrument driver 1702. The drivehousing 1614 may be releasably coupled to the instrument driver 1702 byextending the shaft 1602 through the central aperture 1708 and matingthe drive interface 1716 of the instrument driver 1702 to the driveninterface 1718 of the drive housing 1614, as generally described above.

The carriage 1626 is movable between the first and second ends 1618 a,balong the longitudinal axis A₁ and is thereby able to advance or retractthe end effector 1604 (FIGS. 16 and 17B) relative to the drive housing1614 in z-axis translation. In the illustrated embodiment, z-axistranslation of the carriage 1626 may be accomplished using a cylindricallead screw 3502 forming part of the drive housing 1614. As illustrated,the cylindrical lead screw 3502 comprises a hollow cylinder thatexhibits a generally circular cross section. The cylindrical lead screw3502 is operatively coupled to the first end 1618 a of the drive housing1614 and extends toward the second end 1618 b. In some embodiments, asillustrated, the cylindrical lead screw 3502 stops short of the secondend 1618 b, but may alternatively terminate at the second end 1618 b,without departing from the scope of the disclosure.

The cylindrical lead screw 3502 defines an interior 3504 sized toreceive the splines 1624 a-c and the carriage 1626. Moreover, one ormore cam channels or profiles 3506 (three shown) may be defined on theinner surface of the interior 3504 and configured to receivecorresponding follower pins 3508 (two visible) provided or otherwisedefined on the outer periphery of the carriage 1626. In someembodiments, the follower pins 3508 may comprise tabs or protrusionsextending radially outward from the outer periphery of the carriage1626. The cam profiles 3506 form parallel helical paths that extendalong all or a portion of the interior 3504, and the follower pins 3508may be configured to traverse the cam profiles 3506 and thereby move thecarriage 1626 in z-axis translation. More specifically, the cylindricallead screw 3502 may be configured to rotate about the longitudinal axisA₁ relative to the carriage 1626, and as the cylindrical lead screw 3502rotates, the follower pins 3508 will traverse the corresponding camprofiles 3506. The helical shape of the cam profiles 3506 urges thecarriage 1626 to move proximally or distally in z-axis translation,depending on the rotational direction of the cylindrical lead screw3502.

In the illustrated embodiment, the cylindrical lead screw 3502 may berotated through actuation of a drive input associated with the drivehousing 1614 and arranged in the first end 1618 a. More particularly,the drive housing 1614 may include a fifth drive input 1636 e matablewith the fifth drive output 1724 e of the instrument driver 1702. Onceproperly mated, the fifth drive input 1636 e will share an axis ofrotation with the fifth drive output 1724 e to allow the transfer ofrotational torque from the fifth drive output 1724 e to the fifth driveinput 1636 e. A drive gear 3510 is rotatably mounted to the first end1618 a of the drive housing 1614 at the driven interface 1718. The drivegear 3510 may form part of or may otherwise be operatively coupled tothe fifth drive input 1636 e such that rotation of the fifth drive input1636 e via the fifth drive output 1724 e rotates the drive gear 3510.The cylindrical lead screw 3502 includes a driven gear 3512 thatintermeshes with the drive gear 3510 such that rotation of the drivegear 3510 correspondingly drives the driven gear 3512 and therebyrotates the cylindrical lead screw 3502 about the longitudinal axis A₁.

In some embodiments, as illustrated, the driven gear 3512 may comprise aring gear defined on the outer surface of the cylindrical lead screw3502. In other embodiments, however, the ring gear may alternatively bedefined in the interior 3504 and the drive gear 3510 may be arranged tointermesh with the driven gear 3512 within the interior 3504, withoutdeparting from the scope of the disclosure.

In some embodiments, the cam profile(s) 3506 may be uniform (constant)along the axial length of the cylindrical lead screw 3502. In suchembodiments, the cam profile(s) 3506 will be defined at a single commonpitch (slope) between both ends of the cylindrical lead screw 3502. Inother embodiments, however, the pitch of the cam profile(s) 3506 mayvary along the axial length of the cylindrical lead screw 3502. Forexample, a first portion of the cam profile(s) 3506 may be defined at afirst pitch, while a contiguous second portion of the cam profile(s)3506 may be defined at a second pitch different from the first pitch.The second pitch may be more aggressive as compared to the first pitch,for instance. In such embodiments, without changing the angular velocityof the cylindrical lead screw 3502, the carriage 1626 will move fasterin z-axis translation while traversing the second pitch as compared totraversing the first pitch. As will be appreciated, this may proveadvantageous in allowing the operator to advance the end effector (FIG.16) toward a surgical site faster along portions of the cylindrical leadscrew 3502. More particularly, at the end of the insertion and/orretraction stroke, the profile(s) 3506 may be designed (defined) tomechanically slow down the speed of the carriage 1626 to prevent overtravel damage as it approaches a hard stop. Moreover, at the end of theretraction stroke, the profile(s) 3506 may be designed (defined) toincrease the speed of the carriage 1626 to reduce shaft reverse time.This will correspondingly increase the shaft insertion time whenextending the shaft.

In the illustrated embodiment, the cylindrical lead screw 3502 isarranged within the shroud 1640 that extends between the first andsecond ends 1618 a,b of the drive housing 1614. In at least oneembodiment, however, the shroud 1640 may be omitted from the drivehousing 1614. In other embodiments, the cylindrical lead screw 3502 andthe shroud 1640 may comprise the same structure. In such embodiments,the cam profile(s) 3506 may be defined on the inner surface of theshroud 1640, and the shroud 1640 may rotate to facilitate z-axistranslation of the carriage 1626, without departing from the scope ofthe disclosure.

While the cylindrical lead screw 3502 is described herein with referenceto the cam profile(s) 3506 and follower pin(s) 3508, it is contemplatedherein that the cylindrical lead screw 3502 may alternatively comprise aball screw system, without departing from the scope of the disclosure.In such embodiments, the cylindrical lead screw 3502 may comprise a lowfriction, ball bearing filled lead screw system.

Fixed Roll Insertion Guide Structure

FIG. 36A is a perspective view of the instrument driver 1702 of FIGS.17A and 17B, and FIG. 36B is an isometric view of the surgical tool 1600of FIG. 16 releasably coupled to the instrument driver 1702, accordingto one or more embodiments. As briefly discussed above, the instrumentdriver 1702 is configured to attach a surgical tool, such as thesurgical tool 1600, to a surgical robotic arm (e.g., any of the roboticarms 104, 406 described herein). More specifically, the drive interface1716 at the first end 1706 a of the instrument driver 1702 is matablewith the driven interface 1718 (FIG. 17B) provided at the first end 1618a of the drive housing 1614. The end effector 1604 and the shaft 1602can penetrate the instrument driver 1702 by extending through thecentral aperture 1708 defined longitudinally through the body 1704 ofthe instrument driver 1702, and the alignment guides 1710 within thecentral aperture 1708 help angularly orient the surgical tool 1600 tothe proper orientation relative to the instrument driver 1702.

In some embodiments, the drive housing 1614 may be mechanically coupledto the instrument driver 1702 by mating the interlocking features 1720provided at the drive interface 1716 with the complementary-shapedpockets 1722 (FIG. 17B) provided on the driven interface 1718 (FIG. 17B)of the drive housing 1614. Moreover, the instrument driver 1702 includesthe drive outputs 1724 a-d that are matable with the drive inputs 1636a-d (FIG. 17B) of the drive housing 1614 such that, once properly mated,the drive inputs 1636 a-d will share axes of rotation with thecorresponding drive outputs 1724 a-d to allow the transfer of rotationaltorque from the drive outputs 1724 a-d to the corresponding drive inputs1636 a-d.

In the illustrated embodiment, the instrument driver 1702 includes abase 3602 that provides a location to removably mount the instrumentdriver 1702 to a surgical robotic arm of a surgical robotic system. Aswill be appreciated, the base 3602 may exhibit various geometries andsizes to properly mate with and mount to the robotic arm. Mechanical andelectrical connections are provided from the robotic arm to the base3602 and then to various mechanical and electrical components arrangedwithin the instrument driver 1702 to manipulate and/or deliver powerand/or signals from the robotic arm to the surgical tool 1600. Signalsmay include signals for pneumatic pressure, electrical power, electricalsignals, and/or optical signals.

As illustrated, the body 1704 of the instrument driver 1702 provides anouter housing 3604 that can be fixedly attached to the base 3602. Theouter housing 3604 extends generally between the first and second ends1706 a,b of the instrument driver 1702. In some embodiments, asillustrated, the outer housing 3604 can be generally cylindrical inshape. In other embodiments, however, the shape of the outer housing3604 may vary depending on the application. The outer housing 3604 maybe made of a variety of rigid materials including, but not limited to,metals, plastics, composite materials, or any combination thereof.

In some embodiments, the instrument driver 1702 may further include asterile adapter 3606, 3608 that may be used to create a sterile boundarybetween the instrument driver 1702 and the surgical tool 1600. Thesterile adapters 3606, 3608 comprise component parts located at opposingends of the body 1704; the sterile adapter 3608 at the first end 1706 abeing referred as the “instrument sterile adapter,” and the sterileadapted 3606 located at the second end 1706 b being referred to as the“cannula sterile adapter.” The sterile adapter 3606, 3608 may beconfigured to attach a surgical drape (not shown) to the instrumentdriver 1702 when the surgical tool 1600 is secured to the instrumentdriver 1702, and the surgical drape operates to separate the surgicaltool 1600 and the patient from the instrument driver 1702 and thesurgical robotics system. The sterile adapter 3606 may comprise twolayers that essentially rotate along with the surgical tool 1600, andthe surgical drape is positioned between the layers and does not rollwith the sterile adapter 3606 and surgical tool 1600.

The drive interface 1716, the interlocking features 1720, and the driveoutputs 1724 a-d are all contained within or otherwise mounted to a tooldrive assembly 3609 provided at the first end 1706 a of the instrumentdriver 1702 and extending partially into the outer housing 3604. Asdescribed herein, the tool drive assembly 3609 is capable of rotatingindependent of the outer housing 3604 about a rotational axis 3610. Whenthe surgical tool 1600 is mounted to the instrument driver 1702 at thetool drive assembly 3609, the longitudinal axis A₁ of the surgical tool1600 coaxially aligns with the rotational axis 3610 of the tool driveassembly 3609. According to embodiments of the present disclosure, thetool drive assembly 3609 may be actuated to rotate and therebycorrespondingly rotate or “roll” the entire surgical tool 1600 about itslongitudinal axis A₁, as indicated by the arrows 3612 (FIG. 36B).Consequently, actuation of the tool drive assembly 3609 allows theentire surgical tool 1600, including the shaft 1602, the end effector1604, and the drive housing 1614, to continuously roll about thelongitudinal axis A₁ in either angular direction (i.e., clockwise orcounter-clockwise) relative to the base 3602 and the outer housing 3604,which remain stationary. In contrast to other surgical tools where theshaft and the end effector are rotated independent of and relative tothe remaining portions of the surgical tool, the shaft 1602, the endeffector 1604, and the drive housing 1614 are fixed in rotation, whichenables the entire surgical tool 1600 to rotate as a single, monolithicunit.

FIG. 37A is a schematic diagram of an example embodiment of theinstrument driver 1702 of FIGS. 36A-36B, according to one or moreembodiments. Unlike the instrument driver 1702 depicted in FIGS.36A-36B, the instrument driver 1702 of FIG. 37A includes five driveoutputs 1724. Moreover, the drive interface 1716 (FIG. 36A) is omittedin FIG. 37A to enable viewing of the internal components of the tooldrive assembly 3609 and its roll mechanism. As illustrated, the rollmechanism includes a stator gear 3702 and a rotor gear 3704 matable withthe stator gear 3702, and each of the gears 3702, 3704 is positionedbehind the drive interface 1716 (not shown). Actuation of the tool driveassembly 3609 causes the rotor gear 3704 to drive the stator gear 3702and thereby continuously rotate or “roll” the tool drive assembly 3609about the rotational axis 3610 in either angular direction.

More specifically, as illustrated, the stator gear 3702 may comprise aring gear that defines gear teeth along an inner circumference, and therotor gear 3704 is may comprise a circular gear positioned within theinner circumference of the stator gear 3702 and defining gear teethalong an outer circumference. The gear teeth of the stator gear 3702have the same pitch as the gear teeth of the rotor gear 3704 such thatthe gear teeth are matable. Both gears 3702, 3704 may be made of a rigidmaterial, such as a metal or a hard plastic.

The stator gear 3702 is fixedly attached to the tool drive assembly3609, and the rotor gear 3704 is actuatable (rotatable) to inducerotation of the stator gear 3702, which, in turn, correspondinglyrotates the tool drive assembly 3609, including the drive interface 1716(FIG. 36A), the interlocking features 1720 (FIG. 36A), and the driveoutputs 1724 a-d (FIG. 36A). More particularly, the rotor gear 3704 iscoupled to a drive mechanism (e.g., a motor) housed within the outerhousing 3604 that causes the rotor gear 3704 to rotate in clockwise orcounter-clockwise directions, as desired. The drive mechanism mayreceive signals from an integrated controller also arranged within theouter housing 3604. As the drive mechanism causes the rotor gear 3704 torotate, the rotor gear 3704 travels along the gear teeth of the statorgear 3702, thereby causing the tool drive assembly 3609 to rotate. Inthis configuration, the rotor gear 3704 is capable of continuouslyrotating in either direction and thus allows the tool drive assembly3609 to achieve infinite roll about the rotational axis 3610, andthereby simultaneously causing the surgical tool 1600 (FIG. 36B) torotate or “roll”.

FIG. 37B is a cross-sectional side view of the tool driver 1702 of FIG.37A, according to one or more embodiments. As illustrated, the tooldrive assembly 3609 is operatively coupled to or otherwise defines aninner conduit 3706 that defines the central aperture 1708 such thatrotation of the tool drive assembly 3609 simultaneously rotates theinner conduit 3706 about the rotational axis 3610 in the same direction.As described above, the central aperture 1708 receives the shaft 1602(FIG. 36B) of the surgical tool 16 (FIG. 36B). This configuration allowsthe surgical tool 1600 to be continuously rotated or rolled about therotational axis 3610 in either direction with minimal or norestrictions. One or more actuators 3708 (one shown), alternatelyreferred to as “motor stacks”, are arranged about the inner conduit 3706and rotatable therewith as the tool drive assembly 3609 rotates. Theactuators 3708 are designed to drive the rotation of the drive outputs1724. The tool drive assembly 3609 may further include a drive motor3710 configured to drive the rotation of the tool drive assembly 3609within the outer housing 3604.

The tool drive assembly 3609 may further provide or otherwise include aplurality of bearings 3712. Each bearing 3712 comprises a mechanicalcomponent configured to reduce friction between adjacent moving partsand facilitate rotation around the rotational axis 3610. Morespecifically the bearings 3712 allow the tool drive assembly 3609 torotate about the rotational axis 3610 relative to the outer housing3604, which remains generally stationary. One bearing 3712 alone iscapable of supporting the radial or torsional loading as the tool driveassembly 3609 rotates within the outer housing 3604. In the illustratedembodiment, the instrument driver 1702 includes at least two bearings3712 fixedly attached to the tool drive assembly 3609 such that aplurality of components (such as balls or cylinders) within the bearings3712 contact the outer housing 3604. One of the bearings 3712 isarranged at or near the first end 1706 a of the instrument driver 1702and the other bearing 3712 is arranged at or near the second end 1706 b.This configuration improves rigidity and support between the first endand the second ends of the tool drive assembly 3609 as the tool driveassembly 3609 rotates within the outer housing 3604. Alternateembodiments may include additional bearings that provide additionalsupport along the length of the tool drive assembly 3609, such as alongthe length of the inner conduit 3706.

The tool drive assembly 3609 may also include a plurality of seals 3714and gaskets 3716 configured to seal various surface interfaces toprevent fluids from entering the outer housing at the given interface.The seals 3714, for example, may be arranged at various radialinterfaces between the outer housing 3604 and the tool drive assembly3609, and the gaskets 3716 may be arranged at various axial interfacesbetween the outer housing 3604 and the tool drive assembly 3609. Theseals 3714 and the gaskets 3716 may be made of strong elastomericmaterials (e.g., rubber). In some embodiments, one or more of the seals3714 may comprise O-rings, for example, but may alternatively compriseany other suitable type of sealing element. As will be appreciated, thisconfiguration and placement of the seals 3714 and gaskets 3716 helps tomaintain sterility of the components within the instrument driver 1702during a surgical procedure.

FIG. 37C illustrates a partially exploded, perspective view of theinternal mechanical and electrical components of the instrument driver1702, according to one or more embodiments. The internal mechanical andelectrical components of the instrument driver 1702 include a pluralityof the actuators 3708, the drive motor 3710 (partially visible), atorque sensor (not shown), a torque sensor amplifier 3718, a slip ring3720, a plurality of encoder boards 3722, a plurality of motor powerboards 3724, and an integrated controller 3726.

Each actuator 3708 may be coupled to a corresponding drive output 1724via a drive shaft 3728. In the illustrated embodiment, the instrumentdriver 1702 includes five drive outputs 1724 and thus five actuators3708. The drive shaft 3728 may be a keyed shaft such that it includes aplurality of grooves to allow the drive shaft 3728 to securely mate to acorresponding drive output 1724. The actuator 3708 causes the driveshaft 3728 to rotate in a clockwise or counter-clockwise direction,thereby causing the respective drive output 1724 to similarly rotate. Insome embodiments, the drive shaft 3728 may be torsionally rigid butspring compliant, thus allowing the drive shaft 3728 and thecorresponding drive output 1724 to rotate and also axially retract andprotract within the tool drive assembly 3609. Each actuator 3708 mayreceive electrical signals from the integrated controller 3726indicating the direction and amount to rotate the drive shaft 3728.

The drive motor 3710 is configured to drive the rotation of the tooldrive assembly 3609 within the outer housing 3604. The drive motor 3710may be structurally equivalent to one of the actuators 3708, except thatit is operatively coupled to the rotor gear 3704 and designed to drivethe stator gear 3702 and thereby rotate the tool drive assembly 3609relative to the outer housing 3604, as generally described above. Thedrive motor 3710 causes the rotor gear 3704 to rotate in a clockwise orcounter-clockwise direction, thereby causing the rotor gear 3704 totravel about the gear teeth of the stator gear 3702. This configurationallows the tool drive assembly 3609 to continuously roll or rotatewithout being hindered by potential wind-up of cables or pull-wires. Thedrive motor 3710 may receive electrical signals from the integratedcontroller 3726 indicating the direction and amount to rotate the rotorgear 3704.

The torque sensor measures the amount of torque produced on the rotatingtool drive assembly 3609. In some embodiments, the torque sensor may becapable of measuring torque in both clockwise and counter-clockwisedirections. The torque sensor amplifier 3718 comprises circuitry foramplifying the signal that measures the amount of torque produced on therotating tool drive assembly 3609. In some embodiments, the torquesensor is mounted to the drive motor 3710.

Referring to FIG. 37D, with continued reference to FIG. 37C, illustratedis a partially exploded, perspective view of the internal electricalcomponents of the instrument driver 1702, according to one or moreembodiments. The slip ring 3720 facilitates the transfer of electricalpower and signals from a stationary structure to a rotating structure.More specifically, in the illustrated embodiment, the slip ring 3720 isstructured as a ring including a central hole that is configured toalign with the central aperture 1708 of the tool drive assembly 3609. Afirst side of the slip ring 3720 includes a plurality of concentricgrooves 3730 while a second, opposite side of the slip ring 3720includes a plurality of electrical components for the electricalconnections provided from the robotic arm and the base 3602.

The slip ring 3720 is secured to the outer housing 3604 at a specificdistance from portions of the tool drive assembly 3609 to allocate spacefor electrical connections and interaction. The plurality of concentricgrooves 3730 are configured to mate with a plurality of brushes 3732attached to the integrated controller 3726, which operates as thecomputing device within the tool drive assembly 3609. Contact betweenthe grooves 3730 and the brushes 3732 enables the transfer of electricalpower and signals from the robotic arm to the slip ring 3720, and fromthe slip ring 3720 to the integrated controller 3726. As a result of thereceived signals, the integrated controller 3726 is then configured tosend various signals to respective components within the tool driveassembly 3609 to cause operation of the surgical tool 1600 (FIG. 36B).

The plurality of encoder boards 3722 read and process the signalsreceived through the slip ring 3720 from the surgical robotic system.Signals received from the surgical robotic system may include signalsindicating the amount and direction of rotation of the surgical tool1600 (FIG. 36B), signals indicating the amount and direction of rotationof the end effector 1604 (FIG. 36B), signals operating a light source onthe surgical tool 1600, signals operating a video or imaging device onthe surgical tool 1600, and other signals designed to operate variousfunctionalities of the surgical tool 1600. The configuration of theencoder boards 3722 allows the entire signal processing to be performedcompletely in the tool drive assembly 3609. The plurality of motor powerboards 3724 each comprises circuitry for providing power to theactuators 3708. In some embodiments, the functions of the encoder boards3722 and the integrated controller 3726 may be distributed in adifferent manner than is described here, such that the encoder boards3722 and the integrated controller 3726 may perform the same functionsor some combination thereof.

In the illustrated embodiment, the tool drive assembly 3609 includes twoencoder boards 3722, the torque sensor amplifier 3718, and three motorpower boards 3724. These components are secured to the integratedcontroller 3726 and extend perpendicularly from the integratedcontroller 3726. This configuration provides room for the actuators 3708and the drive motor 3710 to be positioned within the confines of thetool drive assembly 3609.

FIG. 38 is a zoomed-in, perspective view of various electricalcomponents of the instrument driver 1702, according to one or moreembodiments. More specifically, the enlarged, zoomed-in view depictscomponent parts that facilitate roll indexing of the tool drive assembly3609. Roll indexing monitors the angular position of the tool driveassembly 3609 relative to the outer housing 3604 such that the positionand angular orientation of the surgical tool 1600 (FIG. 36B) may beknown in real-time by the surgical robotics system. As illustrated, theroll indexing mechanism includes a micro switch 3802 and one or morebosses 3804 one shown). The micro switch 3802 may be arranged on thetool drive assembly 3609, and the boss(es) 3804 may be positioned on theouter housing 3604 and configured to contact the micro switch 3802 asthe tool drive assembly 3609 rotates and brings the micro switch intoproximity of the boss(es) 3804. Once contact between the micro switch3802 and the boss(es) 3804 occurs, the micro switch 3802 is activatedand records the time and angular orientation of the tool drive assembly3806. Each boss 3804 serves as a single reference point for the microswitch 3802 about the inner circumference of the outer housing 3604.

In other embodiments, the instrument driver 1702 may include other meansto determine rotational position, such as through the use of a dedicatedservo operatively coupled to the rotational drive motor 3710 (FIGS.37B-37C). Alternatively, absolute rotational position could bedetermined by using an annular ring encoder, as generally known by thoseskilled in the art.

Robotic Instrument with Torsion Cable Drives for Carriage-BasedArchitecture

FIGS. 39A and 39B are partial cross-sectional side views of anotherexample of the drive housing 1614 of FIG. 16, according to one or moreadditional embodiments. As illustrated, the drive housing 1614 includesthe first and second ends 1618 a,b, and the instrument driver 1702 canbe removably coupled to the drive housing 1614 at the first end 1618 a.The lead screw 1622 extends longitudinally between the first and secondends 1618 a,b, and the carriage 1626 is movably mounted to the leadscrew 1622 at the carriage nut 1634 to allow the carriage 1626 totraverse the lead screw 1622 along the longitudinal axis A₁. The shaft1602 extends distally from the carriage 1626 through the first end 1618a of the drive housing 1614 and subsequently through the centralaperture 1708 of the instrument driver 1702 (when mounted). The drivehousing 1614 may be releasably coupled to the instrument driver 1702 byextending the shaft 1602 through the central aperture 1708 and matingthe drive interface 1716 of the instrument driver 1702 to the driveninterface 1718 of the drive housing 1614, as generally described above.

In the illustrated embodiment, the driven interface 1718 of the drivehousing 1614 includes a first drive input 3902 a and a second driveinput 3902 b, and the drive interface 1716 includes a first drive output3904 a and a second drive output 3904 b. The drive inputs 3902 a,b maybe substantially similar to the drive inputs 1636 a-d of FIGS. 16 and17B, and the drive outputs 3904 a,b may be substantially similar to thedrive outputs 1724 a-d of FIG. 17B. Accordingly, the drive inputs 3902a,b may be matable with the drive outputs 3904 a,b such that movement(rotation) of a given drive output 3904 a,b correspondingly moves(rotates) the associated drive input 3902 a,b. While only two driveinputs 3902 a,b and two drive outputs 3904 a,b are depicted, more orless than two may be included in the drive housing 1614, withoutdeparting from the scope of the disclosure.

The first drive input 3902 a is operatively coupled to the lead screw1622 such that rotation of the first drive input 3902 a (via rotation ofthe first drive output 3904 a) correspondingly rotates the lead screw1622 in the same angular direction. As the lead screw 1622 rotates, thecarriage nut 1634 is urged to axially traverse the lead screw 1622 andsimultaneously advance or retract the carriage 1626 along thelongitudinal axis A₁, depending on the rotational direction of the leadscrew 1622. Moreover, as the carriage 1626 advances or retracts, theshaft 1602 and the end effector 1604 (FIGS. 16 and 17A-17B) arranged atthe distal end of the shaft 1602 correspondingly moves distally orproximally (i.e., z-axis translation).

In the illustrated embodiment, an activating mechanism 3906 is housed inor otherwise forms part of the carriage 1626, and the second drive input3902 b is operatively coupled to the activating mechanism 3906 such thatrotation of the second drive input 3902 b (via rotation of the seconddrive output 3904 b) causes the activating mechanism 3906 to actuate(operate). The activating mechanism 3906 may be similar to any of theactivating mechanisms 1638 a-c described herein with reference to FIG.16 and other figures. Accordingly, the activating mechanism 3906 may beoperable to carry out one or more functions of the end effector 1604(FIGS. 16 and 17A-17B), such as opening or closing the jaws 1610, 1612(FIGS. 16 and 17A-17B), articulating the end effector 1604 at the wrist1606 (FIG. 16), or advancing or retracting the knife 2702 (FIG. 27) atthe end effector 1604. In the illustrated embodiment, actuating theactivating mechanism 3906 may cause a firing rod 3908 (similar to thefiring rod 2506 of FIGS. 25 and 26) to move along the longitudinal axisA₁ and correspondingly move the knife 2702 in the same direction, thuscausing the knife 2702 to “fire”.

As illustrated, the activating mechanism 3906 may include a drive gear3910 rotatably mounted to the carriage 1626 and configured to drive adriven gear 3912 also rotatably mounted to the carriage 1626. The driveand driven gears 3910, 3912 may each define gear teeth and, in someembodiments, the drive gear 3910 may be positioned to directly intermeshwith the driven gear 3912. In other embodiments, however, one or moreidler gears (not shown) may interpose the drive gear 3910 and the drivengear 3912 and may otherwise transfer torque from the drive gear 3910 tothe driven gear 3912 via an intermeshed gearing arrangement. The drivengear 3912 may be operatively coupled to the firing rod 3908 such thatrotation of the driven gear 3912 (via rotation of the drive gear 3912)causes the firing rod 3908 to translate along the longitudinal axis A₁and thereby cause an associated cutting element or knife to fire.

In order to transmit torsional (rotational) forces or loading from thesecond drive input 3902 b to the activating mechanism 3906 and, moreparticularly, to the drive gear 3910, the drive housing 1614 may furtherinclude a torsion cable 3914 that extends between the second drive input3902 b and the drive gear 3910. The torsion cable 3914 may comprise aflexible wire or filament having a first end 3916 a coupled to thesecond drive input 3902 b and a second end 3916 b coupled to the drivegear 3910. The torsion cable 3914 may be capable of transmittingtorsional loads from the first end 3916 a, as driven by rotation(actuation) of the second drive input 3902 b, to the second end 3916 band thereby cause the drive gear 3910 to rotate.

A basic example of the torsion cable 3914 is the type of cabletraditionally used in vehicle speedometer or tachometer systems; a cablethat is flexible, but strong enough to transmit torque from one end tothe opposite end even when extending in a non-linear path. The torsioncable 3914 may be made of a variety of materials including, but notlimited to, stainless steel and tungsten.

The torsion cable 3914 has a fixed length, and to allow torque to betransmitted between the first and second ends 1916 a,b, the torsioncable 3914 must be maintained in constant tension during operation. Toaccomplish this, the drive housing 1614 may further include a constanttension or tensioning system that includes a tension pulley 3918, astationary pulley 3920, one or more carriage pulleys 3922, and acarriage cable 3924. As illustrated, the stationary pulley 3920 iscoupled or anchored to the drive housing 1614 at or near the first end1618 a, and the torsion cable 3914 is routed through the tension andstationary pulleys 3918, 3920 in the general path/shape of an “S” curve.More specifically, the torsion cable 3914 is coupled to and extends fromthe second drive input 3902 b and is routed around the tension pulley3918 to extend toward the stationary pulley 3920. The torsion cable 3914is then routed around the stationary pulley 3920 and extends to thedrive gear 3910 where it is fixed. Any torsional loading assumed by thetorsion cable 3914 at the first end 3916 a, via rotation (actuation) ofthe second drive input 3902 b, will be transmitted to the second end3916 b of the torsion cable 3914 through the tension and stationarypulleys 3918, 3920 to rotate the drive gear 3910 and thereby cause theactivating mechanism 3906 to actuate (operate); e.g., to perform variousinstrument specific functions, such as knife firing, jaw opening andclosing, energy activation, wristed motions, etc.

The tension pulley 3918 is suspended within the drive housing 1614 onthe carriage cable 3924 to help maintain constant tension in the torsioncable 3914 during operation. More specifically, the carriage cable 3924has a first end 3926 a coupled to the tension pulley 3918 and a secondend 3926 b coupled to the carriage 1626. The carriage cable 3924 isrouted through the carriage pulley(s) 3922, which may be coupled oranchored to the drive housing 1614, such as at or near the second end1618 b. In the illustrated embodiment, there are two carriage pulleys3922, but there could alternatively be more or less than two carriagepulleys 3922, without departing from the scope of the disclosure.Because the second end 3916 b of the torsion cable 3914 is coupled toand travels with the carriage 1626, extending the carriage cable 3914between the carriage 1626 and the tension pulley 3918 forces the tensionpulley 3918 and the carriage 1626 to move in opposite axial directionswhile simultaneously helping to maintain tension in the torsion cable3914 during operation.

Example operation of the drive housing 1614 is now described withcontinued reference to FIGS. 39A-39B. In FIG. 39A, the lead screw 1622is rotated in a first angular direction 3928 a (via operation of thefirst drive input 3902 a), which causes the carriage 1626 to moveproximally, as indicated by the arrow 3930 a. As the carriage 1626 movesproximally 3930 a, the carriage cable 3924 is fed (routed) through thecarriage pulley(s) 3922 and allows the tension pulley 3918 to descenddistally, as indicated by the arrow 3930 b. Since the second end 3916 bof the torsion cable 3914 is coupled to the carriage 1626, the torsioncable 3914 is fed (routed) through the tension and stationary pulleys3918, 3920 as the carriage 1626 moves proximally 3930 a, and the tensionpulley 3918 helps maintain the torsion cable 3914 in constant tension asit moves distally 3930 b. Accordingly, constant tension is maintained inthe torsion cable 3914 while the carriage 1626 moves proximally 3930 aor while it remains stationary. Consequently, the activating mechanism3906 may be operated at all times during operation of the drive housing1614, such as when the carriage 1626 moves or is idle. In someembodiments, a channel or slot (not shown) may be defined within asidewall or other portion of the drive housing 1614 to help guide thetranslational direction of the tension pulley 3918. In addition, a litetension spring could be added to assist movement of the tension pulley3918.

Similarly, in FIG. 39B, the lead screw 1622 is rotated in a secondangular direction 3928 b (via operation of the first drive input 3902a), opposite the first angular direction 3928 a (FIG. 39A), which causesthe carriage 1626 to move distally 3930 b. As the carriage 1626 movesdistally 3930 b, the carriage cable 3924 is fed (routed) through thecarriage pulley(s) 3922 and allows the tension pulley 3918 to ascendproximally 3930 a. Since the second end 3916 b of the torsion cable 3914is coupled to the carriage 1626, the torsion cable 3914 is fed (routed)through the tension and stationary pulleys 3918, 3920 as the carriage1626 moves distally 3930 b, and the tension pulley 3918 helps maintainthe torsion cable 3914 in constant tension as it moves proximally 3930a. Accordingly, constant tension is maintained in the torsion cable 3914while the carriage 1626 moves distally 3930 b or while it remainsstationary. Moreover, as mentioned above, a channel or slot (not shown)may be defined within a sidewall or other portion of the drive housing1614 to help guide the translational direction of the tension pulley3918.

FIGS. 40A and 40B are partial cross-sectional side views of anotherexample of the drive housing 1614 of FIG. 16, according to one or moreadditional embodiments. The drive housing 1614 of FIGS. 40A-40B issimilar in some respects to the embodiment of the drive housing 1614depicted in FIGS. 39A-39B and therefore may be best understood withreference thereto, where like numerals will correspond to similarcomponents not described again. As illustrated, the drive housing 1614includes the first and second ends 1618 a,b, and the instrument driver1702 can be removably coupled to the drive housing 1614 at the first end1618 a. The lead screw 1622 extends longitudinally between the first andsecond ends 1618 a,b, and the carriage 1626 is movably mounted to thelead screw 1622 at the carriage nut 1634 to allow the carriage 1626 totraverse the lead screw 1622 along the longitudinal axis A₁. The shaft1602 extends distally from the carriage 1626 through the first end 1618a of the drive housing 1614 and subsequently through the centralaperture 1708 of the instrument driver 1702 (when mounted). The drivehousing 1614 may be releasably coupled to the instrument driver 1702 byextending the shaft 1602 through the central aperture 1708 and matingthe drive interface 1716 of the instrument driver 1702 to the driveninterface 1718 of the drive housing 1614, as generally described above.

In the illustrated embodiment, the driven interface 1718 of the drivehousing 1614 includes a drive input 4002 and the drive interface 1716includes a drive output 4004. The drive input 4002 may be substantiallysimilar to the drive inputs 1636 a-d of FIGS. 16 and 17B, and the driveoutput 4004 may be substantially similar to the drive outputs 1724 a-dof FIG. 17B. Accordingly, the drive input 4002 may be matable with thedrive output 4004 such that movement (rotation) of the drive output 4004correspondingly moves (rotates) the associated drive input 4002.

In the illustrated embodiment, an activating mechanism 4006 is housed inor otherwise forms part of the carriage 1626, and the drive input 4002is operatively coupled to the activating mechanism 4006 such thatrotation of the drive input 4002 (via rotation of the drive output 4004)causes the activating mechanism 4006 to actuate (operate). While theactivating mechanism 4006 may be similar to any of the activatingmechanisms 1638 a-c described herein with reference to FIG. 16 and otherfigures, in the illustrated embodiment, the activating mechanism 4006 isconfigured to rotate the lead screw 1622 and thereby cause axialtranslation of the carriage 1626 along the longitudinal axis A₁.

More specifically, the activating mechanism 4006 includes a drive gear4008 rotatably mounted to the carriage 1626 and configured to drive adriven gear 4010 also rotatably mounted to the carriage 1626. In someembodiments, the drive gear 4008 may be positioned to directly intermeshwith the driven gear 4010. In other embodiments, however, one or moreidler gears 4012 (one shown) may interpose the drive gear 4008 and thedriven gear 4010 and may otherwise transfer torque from the drive gear4008 to the driven gear 4010 via an intermeshed gearing arrangement. Insome embodiments, the driven gear 4010 forms part of or is otherwisedefined on the outer circumference of the carriage nut 1634 such thatrotation of the driven gear 4010 correspondingly rotates the carriagenut 1634 relative to the lead screw 1622, which remains stationary. Asthe carriage nut 1634 rotates, the carriage 1626 is urged to moveaxially along the longitudinal axis A₁, depending on the rotationaldirection of the carriage nut 1634.

In order to transmit torsional (rotational) forces or loading from thedrive input 4002 to the activating mechanism 4006 and, moreparticularly, to the drive gear 4008, the torsion cable 3914 extendsbetween the drive input 4002 and the drive gear 4008. Moreover, thetorsion cable 3914 is maintained in constant tension with the tensioningsystem described above with reference to FIGS. 39A-39B. Morespecifically, the torsion cable 3914 is coupled to and extends from thedrive input 4002 and is routed around the tension pulley 3918 to extendtoward the stationary pulley 3920. The torsion cable 3914 is then routedaround the stationary pulley 3920 and extends to the drive gear 4008where it is fixed. Any torsional loading assumed by the torsion cable3914 at its first end 3916 a, via rotation (actuation) of the driveinput 4002, will be transmitted to its second end 3916 b through thetension and stationary pulleys 3918, 3920 to rotate the drive gear 4008and thereby cause the activating mechanism 4006 to actuate (operate).

Moreover, the tension pulley 3918 is again suspended within the drivehousing 1614 on the carriage cable 3924 to help maintain constanttension in the torsion cable 3914 during operation. More specifically,the carriage cable 3924 extends from the tension pulley 3918, throughthe carriage pulley(s) 3922, and to the carriage 1626. Because thesecond end 3916 b of the torsion cable 3914 is coupled to and travelswith the carriage 1626, extending the carriage cable 3914 between thecarriage 1626 and the tension pulley 3918 forces the tension pulley 3918and the carriage 1626 to move in opposite axial directions whilesimultaneously helping to maintain tension in the torsion cable 3914during operation.

Example operation of the drive housing 1614 is now described withcontinued reference to FIGS. 40A-40B. In FIG. 40A, the torsion cable3914 is rotated in a first angular direction (via operation of the driveinput 4002), which causes the drive gear 4008 to rotate and therebyrotate the driven gear 4010. Rotating the driven gear 4010correspondingly rotates the carriage nut 1634 relative to the stationarylead screw 1622, which urges the carriage 1626 to move proximally 3930 aalong the lead screw 1622. As the carriage 1626 moves proximally 3930 a,the carriage cable 3924 is fed (routed) through the carriage pulley(s)3922 and allows the tension pulley 3918 to descend distally 3930 b.Since the second end 3916 b of the torsion cable 3914 is coupled to thecarriage 1626, the torsion cable 3914 is fed (routed) through thetension and stationary pulleys 3918, 3920 as the carriage 1626 movesproximally 3930 a, and the tension pulley 3918 helps maintain thetorsion cable 3914 in constant tension as it moves distally 3930 b.

Similarly, in FIG. 40B, the torsion cable 3914 is rotated in a secondangular direction (via operation of the drive input 4002) opposite thefirst angular direction, which causes the drive gear 4008 to rotate andthereby rotate the driven gear 4010. Rotating the driven gear 4010correspondingly rotates the carriage nut 1634 relative to the stationarylead screw 1622, which urges the carriage 1626 to move distally 3930 balong the lead screw 1622. As the carriage 1626 moves distally 3930 b,the carriage cable 3924 is fed (routed) through the carriage pulley(s)3922 and allows the tension pulley 3918 to ascend proximally 3930 a.Since the second end 3916 b of the torsion cable 3914 is coupled to thecarriage 1626, the torsion cable 3914 is fed (routed) through thetension and stationary pulleys 3918, 3920 as the carriage 1626 movesdistally 3930 b, and the tension pulley 3918 helps maintain the torsioncable 3914 in constant tension as it moves proximally 3930 a.

FIG. 40C is an alternative embodiment of the drive housing 1614 of FIGS.40A-40B, but could alternatively be applicable to the drive housing 1614of 39A-39B, without departing from the scope of the disclosure. As withthe embodiment of FIGS. 40A-40B, the tension pulley 3918 is suspendedwithin the drive housing 1614 at the first end 3926 a of the carriagecable 3924 to help maintain constant tension in the torsion cable 3914during operation. Moreover, the carriage cable 3924 is routed around thecarriage pulley 3922. Unlike the embodiment of FIGS. 40A-40B, however,the carriage cable 3924 is further routed around a mounted pulley 4012coupled or fixed to the carriage 1626 and the second end 3926 b of thecarriage cable 3924 is fixed to the drive housing 1614, such as at ornear the second end 1618 b thereof. Including the mounted pulley 4012results in three routed lengths of the carriage cable 3924, which equalsthree routed lengths of the torsion cable 3914. This helps to ensurethat the same length is paid out as is consumed by axial translation theshaft 1602.

FIGS. 41A-41C are partial cross-sectional side views of alternativeembodiments of the drive housing 1614 of FIG. 16, according to one ormore additional embodiments. In the illustrated embodiments, the drivehousing 1614 includes a carriage 4102 similar in some respects to thecarriage 1626 of FIG. 16. For instance, the carriage 4102 is movable thebetween first and second ends 1618 a,b of the drive housing 1614 alongthe longitudinal axis A₁ (i.e., z-axis translation), and the shaft 1602extends distally from the carriage 4102. Accordingly, as the carriage4102 moves along the longitudinal axis A₁, the carriage 4102 is therebyable to advance or retract an end effector (e.g., the end effector 1604of FIG. 16) attached to the distal end of the shaft 1602 relative to thedrive housing 1614.

In FIG. 41A, the carriage 4102 includes a carriage nut 4104 rotatablymounted to the lead screw 1622. The carriage nut 4104 may be similar insome respects to the carriage nut 1634 of FIG. 16. For instance, thecarriage nut 4104 defines corresponding internal helical threading (notshown) matable with the outer helical threading of the lead screw 1622and, as a result, rotation of the lead screw 1622 causes the carriagenut 4104 to traverse the lead screw 1622 and simultaneously cause thecarriage 4102 to advance or retract along the longitudinal axis A₁, andcorrespondingly advance or retract the shaft 1602.

The carriage nut 4104 is located at or near a distal end 4106 of thecarriage 4102. During operation of the drive housing 1614, such asactivating various functions of the end effector 1604 (FIG. 16), thecarriage 4102 may experience various torsional and axial forces F thatcause the carriage 4102 to rotate or shift in the direction R. Shiftingthe carriage 4102 in the direction R can bind or inhibit the movement ofthe carriage 4102 along the drive housing 1614. According to embodimentsof the present disclosure, the carriage 4102 may be stabilized androtation in the direction R minimized or eliminated by having portionsof the carriage nut 4104 located at or near the distal and proximal endsof the carriage 4102. In such embodiments, the carriage 4102 may bemounted to the lead screw 1622 at two or more spaced-apart locations orotherwise spanning a substantial length of the carriage 4102, asdescribed in greater detail below.

In FIG. 41B, the carriage 4102 includes at least two carriage nutsoperable to increase the stability of the carriage 4102, i.e., minimizetwisting and rotation of the carriage 4102 about the lead screw 1622.More specifically, the carriage 4102 may include a first carriage nut4104 a and a second carriage nut 4104 b. The first carriage nut 4104 amay be positioned at or near the distal end 4106 of the carriage 4102and the second carriage nut 4104 b is positioned at or near a proximalend 4108 of the carriage 4102. The carriage nuts 4104 a,b are eachmounted to the rotatable lead screw 1622 and are each supported by thecarriage 4102 in a spaced apart relationship, generally located onopposite ends of the carriage 4102.

In embodiments where the carriage 4102 is composed of a plurality oflayers, a carriage nut may be present on at least two layers forfacilitating translation of the carriage in response to rotation of thelead screw 1622. In FIG. 41B, for example, the carriage 4102 includesfour stacked layers, depicted as a first layer 4110 a, a second layer4110 b, a third layer 4110 c, and a fourth layer 4110 d. While fourlayers are illustrated, it is to be appreciated that the number oflayers of the carriage 4102 may be more or less than four, withoutdeparting from the scope of the disclosure. The first layer 4110 a maybe alternately referred to as the “distal layer 4110 a,” and the fourthlayer 4110 d may be alternately referred to as the “proximal layer 4110d”. In such embodiments, the first carriage nut 4104 a may be coupled tothe distal layer 4110 a and the second carriage nut 4104 b may becoupled to the proximal layer 4110 d. While not shown, it iscontemplated herein to include additional carriage nuts coupled to theother layers, e.g., the second and third layers 4110 b,c.

In some embodiments, as illustrated, the first carriage nut 4104 a maybe coupled to or otherwise encompass or span portions of two or morelayers of the carriage 4102. In FIG. 41B, the first carriage nut 4104 ais depicted as being coupled to or otherwise supported by the distallayer 4110 a, but also extends into the adjacent second layer 4110 b.Accordingly, in some embodiments, the first carriage nut 4104 a mayextend across two layers 4110 a, 4110 b and the second carriage nut 4104b may be secured to a single layer 4110 d.

In FIG. 41C, the carriage 4102 includes a platform layer 4110 e thatsupports a plurality of other layers, shown as layers 4110 f, 4110 g,and 4110 h. In the illustrated embodiment, a portion of the platformlayer 4110 e extends generally between the distal and proximal ends4106, 4108 of the carriage 4102, but may alternatively extend only aportion of the distance between the distal and proximal ends 4106, 4108,or may extend further than the distance between the distal and proximalends 4106, 4108, without departing from the scope of the disclosure.

In the illustrated embodiment, the carriage 4102 includes an elongatedcarriage nut 4104 c that substantially extends from the distal end 4106to the proximal end 4108 of the carriage 4102. The carriage nut 4104 cis mounted to the platform layer 4110 e and is thus responsible for thetranslation of the coupled carriage layers 4110 e-h along the lead screw1622. In some embodiments, the carriage nut 4104 may extend along theentire axial length of the platform layer 4110 e, but may alternativelyextend along only a portion of the axial length of the platform layer4110 e. Although not illustrated, it is contemplated that a second layerin a stack of two or more layers may incorporate an elongated carriagenut, similar to the elongated nut 4104, having a proximal portion 4112 aand a distal portion 4112 b and supporting a first layer distally, and athird layer proximally.

4. Implementing Systems and Terminology.

Implementations disclosed herein provide systems, methods and apparatusfor instruments for use with robotic systems. It should be noted thatthe terms “couple,” “coupling,” “coupled” or other variations of theword couple as used herein may indicate either an indirect connection ora direct connection. For example, if a first component is “coupled” to asecond component, the first component may be either indirectly connectedto the second component via another component or directly connected tothe second component.

The methods disclosed herein comprise one or more steps or actions forachieving the described method. The method steps and/or actions may beinterchanged with one another without departing from the scope of theclaims. In other words, unless a specific order of steps or actions isrequired for proper operation of the method that is being described, theorder and/or use of specific steps and/or actions may be modifiedwithout departing from the scope of the claims.

As used herein, the term “plurality” denotes two or more. For example, aplurality of components indicates two or more components. The term“determining” encompasses a wide variety of actions and, therefore,“determining” can include calculating, computing, processing, deriving,investigating, looking up (e.g., looking up in a table, a database oranother data structure), ascertaining and the like. Also, “determining”can include receiving (e.g., receiving information), accessing (e.g.,accessing data in a memory) and the like. Also, “determining” caninclude resolving, selecting, choosing, establishing and the like.

The phrase “based on” does not mean “based only on,” unless expresslyspecified otherwise. In other words, the phrase “based on” describesboth “based only on” and “based at least on.”

As used herein, the terms “generally” and “substantially” are intendedto encompass structural or numeral modification which do notsignificantly affect the purpose of the element or number modified bysuch term.

To aid the Patent Office and any readers of this application and anyresulting patent in interpreting the claims appended herein, applicantsdo not intend any of the appended claims or claim elements to invoke 35U.S.C. 112(f) unless the words “means for” or “step for” are explicitlyused in the particular claim.

The foregoing previous description of the disclosed implementations isprovided to enable any person skilled in the art to make or use thepresent invention. Various modifications to these implementations willbe readily apparent to those skilled in the art, and the genericprinciples defined herein may be applied to other implementationswithout departing from the scope of the invention. For example, it willbe appreciated that one of ordinary skill in the art will be able toemploy a number corresponding alternative and equivalent structuraldetails, such as equivalent ways of fastening, mounting, coupling, orengaging tool components, equivalent mechanisms for producing particularactuation motions, and equivalent mechanisms for delivering electricalenergy. Thus, the present invention is not intended to be limited to theimplementations shown herein but is to be accorded the widest scopeconsistent with the principles and novel features disclosed herein.

What is claimed is:
 1. A robotic surgical tool, comprising: a drivehousing having a first end, a second end, and a lead screw extendingbetween the first and second ends; a carriage movably mounted to thelead screw at a carriage nut secured to the carriage; an activatingmechanism including a drive gear rotatably mounted to the carriage androtatable to actuate the activating mechanism; and a torsion cableextending between the drive gear and a drive input arranged at the firstend, wherein rotating the drive input rotates the torsion cable andthereby transmits a torsional load along the torsion cable to the drivegear to actuate the activating mechanism.
 2. The robotic surgical toolof claim 1, further comprising an instrument driver arranged at an endof a robotic arm and matable with the drive housing at the first end,the instrument driver providing a drive output matable with the driveinput such that rotation of the drive output correspondingly rotates thedrive input and thereby rotates the torsion cable to actuate theactivating mechanism.
 3. The robotic surgical tool of claim 2, whereinthe drive input is a first drive input and the drive output is a firstdrive output, the robotic surgical tool further comprising: a seconddrive input arranged at the first end and operatively coupled to thelead screw such that rotation of the second drive input correspondinglyrotates the lead screw; and a second drive output provided by theinstrument driver and matable with the second drive input such thatrotation of the second drive output correspondingly rotates the seconddrive input and thereby rotates the lead screw.
 4. The robotic surgicaltool of claim 1, further comprising: an elongate shaft extending fromthe carriage and penetrating the first end; an end effector arranged ata distal end of the shaft; and a wrist interposing the shaft and the endeffector, wherein actuating the activating mechanism causes at least oneof the following to occur: opening or closing jaws of the end effector;articulating the end effector at the wrist; and advancing or retractinga knife at the end effector.
 5. The robotic surgical tool of claim 5,wherein the end effector is selected from the group consisting of asurgical stapler, a tissue grasper, surgical scissors, an advancedenergy vessel sealer, a clip applier, a needle driver, a babcockincluding a pair of opposed grasping jaws, bipolar jaws, a suctionirrigator, an endoscope, a laparoscope, and any combination thereof. 6.The robotic surgical tool of claim 1, further comprising: an elongateshaft extending from the carriage and penetrating the first end; and anend effector arranged at a distal end of the shaft, wherein theactivating mechanism further includes: a driven gear rotatably mountedto the carriage and operatively coupled to the drive gear such thatrotation of the drive gear correspondingly rotates the driven gear; anda firing rod operatively coupled to the driven gear such that rotationof the driven gear causes the firing rod to axially translate along theshaft and cause a knife at the end effector to move.
 7. The roboticsurgical tool of claim 1, further comprising a tensioning system thatincludes: a tension pulley; a stationary pulley anchored to the drivehousing, wherein the torsion cable is routed through the tension andstationary pulleys; one or more carriage pulleys anchored to the drivehousing; and a carriage cable routed through the one or more carriagepulleys and extending between the carriage and the tension pulley,wherein the tension pulley maintains tension in the torsion cable bytraveling in an axial direction opposite the carriage as the carriagetraverses the lead screw.
 8. The robotic surgical tool of claim 1,wherein the activating mechanism further includes a driven gear providedon an outer circumference of the carriage nut and operatively coupled tothe drive gear such that rotation of the drive gear correspondinglyrotates the carriage nut relative to the lead screw and thereby urgesthe carriage to move axially along the lead screw.
 9. The roboticsurgical tool of claim 8, further comprising one or more idler gearsinterposing the drive gear and the driven gear to transfer torque fromthe drive gear to the driven gear.
 10. A method of operating a roboticsurgical tool, comprising: locating the robotic surgical tool adjacent apatient, the robotic surgical tool comprising: a drive housing having afirst end, a second end, and a lead screw extending between the firstand second ends; a carriage movably mounted to the lead screw at acarriage nut secured to the carriage; an activating mechanism includinga drive gear rotatably mounted to the carriage; and a torsion cableextending between the drive gear and a drive input arranged at the firstend; rotating the drive input and thereby rotating the torsion cable;and transmitting a torsional load along the torsion cable to the drivegear as the torsion cable rotates and thereby actuating the activatingmechanism.
 11. The method of claim 10, wherein an instrument driverarranged at an end of a robotic arm is mated with the drive housing atthe first end, and the instrument driver provides a drive output matablewith the drive input, the method further comprising rotating the driveoutput and thereby rotating the drive input and the torsion cable toactuate the activating mechanism.
 12. The method of claim 11, whereinthe drive input is a first drive input and the drive output is a firstdrive output, the method further comprising: rotating a second outputprovided by the instrument driver and thereby rotating a second driveinput arranged at the first end and operatively coupled to the leadscrew; rotating the lead screw as the second drive input rotates; andmoving the carriage along the lead screw as the lead screw rotates. 13.The method of claim 10, wherein the surgical tool further includes anelongate shaft extending from the carriage and penetrating the firstend, an end effector arranged at a distal end of the shaft, and a wristinterposing the shaft and the end effector, and wherein actuating theactivating mechanism comprises at least one of the following: opening orclosing jaws of the end effector; articulating the end effector at thewrist; and advancing or retracting a knife at the end effector.
 14. Themethod of claim 10, wherein the surgical tool further includes anelongate shaft extending from the carriage and penetrating the firstend, an end effector arranged at a distal end of the shaft, the methodfurther comprising: rotating the drive gear with the torsion cable, thedrive gear being operatively coupled to a driven gear rotatably mountedto the carriage, and the driven gear being operatively coupled to afiring rod; rotating the driven gear with rotation of the drive gear andthereby causing the firing rod to axially translate along the shaft; andmoving a knife at the end effector as the firing rod axially translates.15. The method of claim 10, further comprising: maintaining tension inthe torsion cable with a tensioning system that includes: a tensionpulley; a stationary pulley anchored to the drive housing, wherein thetorsion cable is routed through the tension and stationary pulleys; oneor more carriage pulleys anchored to the drive housing; and a carriagecable routed through the one or more carriage pulleys and extendingbetween the carriage and the tension pulley; and moving the tensionpulley in an axial direction opposite the carriage as the carriagetraverses the lead screw.
 16. The method of claim 15, furthercomprising: feeding the torsion cable through the tension and stationarypulleys as the tension pulley moves in the axial direction; and feedingthe carriage cable through the one or more carriage pulleys as thecarriage traverses the lead screw.
 17. The method of claim 10, whereinthe activating mechanism further includes a driven gear provided on anouter circumference of the carriage nut and operatively coupled to thedrive gear, the method further comprising: rotating the drive gear withthe torsion cable and thereby rotating the driven gear; and rotating thecarriage nut as the driven gear rotates and thereby urging the carriageto move axially along the lead screw.
 18. The method of claim 16,further comprising one or more idler gears interposing the drive gearand the driven gear to transfer torque from the drive gear to the drivengear.
 19. A robotic surgical tool, comprising: a drive housing having afirst end, a second end, and a lead screw extending between the firstand second ends; a carriage movably mounted to the lead screw at acarriage nut secured to the carriage; an elongate shaft extending fromthe carriage and penetrating the first end, and an end effector arrangedat a distal end of the shaft; a drive gear rotatably mounted to thecarriage; a driven gear rotatably mounted to the carriage andoperatively coupled to the drive gear such that rotation of the drivegear correspondingly rotates the driven gear; and a firing rodoperatively coupled to the driven gear such that rotation of the drivengear causes the firing rod to axially translate along the shaft andcause a knife at the end effector to move.
 20. The robotic surgical toolof claim 19, further comprising a tensioning system that includes: atension pulley; a stationary pulley anchored to the drive housing,wherein the torsion cable is routed through the tension and stationarypulleys; one or more carriage pulleys anchored to the drive housing; anda carriage cable routed through the one or more carriage pulleys andextending between the carriage and the tension pulley, wherein thetension pulley maintains tension in the torsion cable by traveling in anaxial direction opposite the carriage as the carriage traverses the leadscrew.